Scope authenticated delivery cleanup

bitchat/App/ConversationStore.swift

@@ -426,6 +426,40 @@ final class ConversationStore: ObservableObject {
     @discardableResult
     func setDeliveryStatus(_ status: DeliveryStatus, forMessageID messageID: String) -> Bool {
         guard let ids = conversationIDsByMessageID[messageID] else { return false }
+        return applyDeliveryStatus(status, forMessageID: messageID, among: ids)
+    }
+
+    /// Applies an authenticated delivery/read receipt only to the supplied
+    /// direct-conversation aliases. A colliding message ID in another peer's
+    /// conversation (or a public timeline) must not inherit the receipt.
+    ///
+    /// Stable and ephemeral aliases can temporarily hold the same message
+    /// instance during handoff. The shared helper republishes every targeted
+    /// alias even when the first mutation already changed that instance.
+    @discardableResult
+    func setDeliveryStatus(
+        _ status: DeliveryStatus,
+        forMessageID messageID: String,
+        inDirectPeerAliases peerIDs: Set<PeerID>
+    ) -> Bool {
+        guard !peerIDs.isEmpty,
+              let indexedIDs = conversationIDsByMessageID[messageID] else {
+            return false
+        }
+        let allowedIDs = Set(peerIDs.map { ConversationID.directPeer($0) })
+        return applyDeliveryStatus(
+            status,
+            forMessageID: messageID,
+            among: indexedIDs.intersection(allowedIDs)
+        )
+    }
+
+    private func applyDeliveryStatus(
+        _ status: DeliveryStatus,
+        forMessageID messageID: String,
+        among ids: Set<ConversationID>
+    ) -> Bool {
+        guard !ids.isEmpty else { return false }
         var applied = false
         var skipped: [ConversationID] = []
         for id in ids {

bitchat/Services/Courier/MessageOutboxStore.swift

@@ -110,6 +110,10 @@ final class MessageOutboxStore {
     /// Delivery/read acknowledgments received before a deferred cold-load
     /// reveals the durable queue. Applied to every merge before persistence.
     private var pendingRemovalMessageIDs = Set<String>()
+    /// Peer-scoped acknowledgments received before a deferred cold-load
+    /// reveals the durable queue. Unlike the legacy global tombstones above,
+    /// these must not remove a colliding message ID queued for another peer.
+    private var pendingScopedRemovalMessageIDs: [PeerID: Set<String>] = [:]
     private var recoveryHandler: (@MainActor (Snapshot) -> Void)?
     /// Recovery loaded durable state that MessageRouter has not merged yet.
     /// While true, router saves must union with `cachedSnapshot` instead of
@@ -195,7 +199,7 @@ final class MessageOutboxStore {
                 ? (pendingSnapshot ?? [:])
                 : Self.merge(durable, pendingSnapshot ?? [:]))
             diskState = .loaded
-            if pendingSnapshot != nil || !pendingRemovalMessageIDs.isEmpty {
+            if pendingSnapshot != nil || hasPendingRemovalsLocked {
                 if persistSnapshotAndClearRemovalsLocked(cachedSnapshot) {
                     pendingSnapshot = nil
                     pendingSnapshotIsAuthoritative = false
@@ -212,7 +216,7 @@ final class MessageOutboxStore {
         case .missing:
             cachedSnapshot = applyingPendingRemovalsLocked(pendingSnapshot ?? [:])
             diskState = .loaded
-            if pendingSnapshot != nil || !pendingRemovalMessageIDs.isEmpty {
+            if pendingSnapshot != nil || hasPendingRemovalsLocked {
                 if persistSnapshotAndClearRemovalsLocked(cachedSnapshot) {
                     pendingSnapshot = nil
                     pendingSnapshotIsAuthoritative = false
@@ -235,7 +239,7 @@ final class MessageOutboxStore {
             diskState = .loaded
             cachedSnapshot = applyingPendingRemovalsLocked(pendingSnapshot ?? [:])
             SecureLogger.error("Failed to decode encrypted outbox: \(error)", category: .session)
-            if pendingSnapshot != nil || !pendingRemovalMessageIDs.isEmpty {
+            if pendingSnapshot != nil || hasPendingRemovalsLocked {
                 if persistSnapshotAndClearRemovalsLocked(cachedSnapshot) {
                     pendingSnapshot = nil
                     pendingSnapshotIsAuthoritative = false
@@ -442,6 +446,25 @@ final class MessageOutboxStore {
         lock.unlock()
     }
 
+    /// Records an ack for only the supplied peer aliases. This preserves
+    /// another recipient's queued entry when message IDs happen to collide,
+    /// including while the durable snapshot is hidden by protected data.
+    func recordRemoval(messageID: String, for peerIDs: Set<PeerID>) {
+        guard !peerIDs.isEmpty else { return }
+
+        lock.lock()
+        for peerID in peerIDs {
+            pendingScopedRemovalMessageIDs[peerID, default: []].insert(messageID)
+        }
+        cachedSnapshot = Self.removing(pendingScopedRemovalMessageIDs, from: cachedSnapshot)
+        unseenRecoveredSnapshot = Self.removing(pendingScopedRemovalMessageIDs, from: unseenRecoveredSnapshot)
+        recoveryRouterSnapshot = Self.removing(pendingScopedRemovalMessageIDs, from: recoveryRouterSnapshot)
+        if let pendingSnapshot {
+            self.pendingSnapshot = Self.removing(pendingScopedRemovalMessageIDs, from: pendingSnapshot)
+        }
+        lock.unlock()
+    }
+
     /// Retries a deferred protected-data load. The returned snapshot includes
     /// both durable messages and any messages queued during the locked wake.
     @discardableResult
@@ -478,7 +501,7 @@ final class MessageOutboxStore {
                 : (pendingSnapshotIsAuthoritative ? known : Self.merge(durable, known)))
             cachedSnapshot = merged
             diskState = .loaded
-            if (pendingSnapshot == nil && pendingRemovalMessageIDs.isEmpty) ||
+            if (pendingSnapshot == nil && !hasPendingRemovalsLocked) ||
                 persistSnapshotAndClearRemovalsLocked(merged) {
                 pendingSnapshot = nil
                 pendingSnapshotIsAuthoritative = false
@@ -507,7 +530,7 @@ final class MessageOutboxStore {
                 : known)
             cachedSnapshot = merged
             diskState = .loaded
-            if (pendingSnapshot == nil && pendingRemovalMessageIDs.isEmpty) ||
+            if (pendingSnapshot == nil && !hasPendingRemovalsLocked) ||
                 persistSnapshotAndClearRemovalsLocked(merged) {
                 pendingSnapshot = nil
                 pendingSnapshotIsAuthoritative = false
@@ -539,7 +562,7 @@ final class MessageOutboxStore {
                 : known)
             cachedSnapshot = merged
             diskState = .loaded
-            if (pendingSnapshot == nil && pendingRemovalMessageIDs.isEmpty) ||
+            if (pendingSnapshot == nil && !hasPendingRemovalsLocked) ||
                 persistSnapshotAndClearRemovalsLocked(merged) {
                 pendingSnapshot = nil
                 pendingSnapshotIsAuthoritative = false
@@ -578,6 +601,7 @@ final class MessageOutboxStore {
         pendingSnapshot = nil
         pendingSnapshotIsAuthoritative = false
         pendingRemovalMessageIDs.removeAll()
+        pendingScopedRemovalMessageIDs.removeAll()
         recoveryDeliveryPending = false
         unseenRecoveryPendingPersistence = false
         unseenRecoveredSnapshot = [:]
@@ -742,12 +766,21 @@ final class MessageOutboxStore {
     private func persistSnapshotAndClearRemovalsLocked(_ snapshot: Snapshot) -> Bool {
         guard persistSnapshotLocked(snapshot) else { return false }
         pendingRemovalMessageIDs.removeAll()
+        pendingScopedRemovalMessageIDs.removeAll()
         return true
     }
 
     /// Must be called with `lock` held.
     private func applyingPendingRemovalsLocked(_ snapshot: Snapshot) -> Snapshot {
-        Self.removing(pendingRemovalMessageIDs, from: snapshot)
+        Self.removing(
+            pendingScopedRemovalMessageIDs,
+            from: Self.removing(pendingRemovalMessageIDs, from: snapshot)
+        )
+    }
+
+    /// Must be read with `lock` held.
+    private var hasPendingRemovalsLocked: Bool {
+        !pendingRemovalMessageIDs.isEmpty || !pendingScopedRemovalMessageIDs.isEmpty
     }
 
     private static func removing(_ messageIDs: Set<String>, from snapshot: Snapshot) -> Snapshot {
@@ -760,9 +793,28 @@ final class MessageOutboxStore {
         return filtered
     }
 
+    private static func removing(
+        _ messageIDsByPeer: [PeerID: Set<String>],
+        from snapshot: Snapshot
+    ) -> Snapshot {
+        guard !messageIDsByPeer.isEmpty else { return snapshot }
+        var filtered = snapshot
+        for (peerID, messageIDs) in messageIDsByPeer {
+            guard !messageIDs.isEmpty, let queue = filtered[peerID] else { continue }
+            let remaining = queue.filter { !messageIDs.contains($0.messageID) }
+            filtered[peerID] = remaining.isEmpty ? nil : remaining
+        }
+        return filtered
+    }
+
     private static func excludingKnownMessages(from durable: Snapshot, known: Snapshot) -> Snapshot {
-        let knownIDs = Set(known.values.flatMap { $0.map(\.messageID) })
+        var unseen: Snapshot = [:]
-        return removing(knownIDs, from: durable)
+        for (peerID, durableQueue) in durable {
+            let knownIDs = Set(known[peerID]?.map(\.messageID) ?? [])
+            let remaining = durableQueue.filter { !knownIDs.contains($0.messageID) }
+            if !remaining.isEmpty { unseen[peerID] = remaining }
+        }
+        return unseen
     }
 
     private static func merge(_ durable: Snapshot, _ pending: Snapshot) -> Snapshot {

bitchat/Services/Gateway/BridgeCourierService.swift

@@ -106,13 +106,14 @@ final class BridgeCourierService: ObservableObject {
         dedupKey: String?,
         operationID: UUID?
     )] = []
-    /// Message IDs already published as drops (sender-side dedup) and drop
+    /// Opaque recipient/message keys already published as drops (sender-side
-    /// event IDs already handled (multi-relay dedup). Both persist across
+    /// dedup) and drop event IDs already handled (multi-relay dedup). Both
-    /// relaunches: relays hold drops for the full 24h NIP-40 window and the
+    /// persist across relaunches: relays hold drops for the full 24h NIP-40
-    /// persisted outbox keeps re-depositing, so in-memory-only dedup meant
+    /// window and the persisted outbox keeps re-depositing, so in-memory-only
-    /// every relaunch republished the same message as a fresh drop and every
+    /// dedup meant every relaunch republished the same message as a fresh drop
-    /// gateway relaunch re-delivered the whole backlog (field-verified
+    /// and every gateway relaunch re-delivered the whole backlog
-    /// amplification storm). Entries age out with the 24h drop window.
+    /// (field-verified amplification storm). Entries age out with the 24h drop
+    /// window.
     private var publishedDropKeys: ExpiringIDSet
     private var seenDropEventIDs: ExpiringIDSet
     private var subscriptionOpen = false
@@ -126,7 +127,7 @@ final class BridgeCourierService: ObservableObject {
     }
     /// Sender operations queued locally or awaiting relay confirmation.
     /// The per-attempt ID prevents a stale pre-wipe callback from completing
-    /// a newer attempt for the same message.
+    /// a newer attempt for the same recipient/message pair.
     private var activeDropOperations: [String: ActiveDropOperation] = [:]
     /// Held-envelope publishes have no sender message ID, but still need an
     /// in-flight identity: repeated refreshes inside the relay-OK wait window
@@ -214,11 +215,46 @@ final class BridgeCourierService: ObservableObject {
 
     // MARK: - Sender role
 
+    /// Stable, opaque sender-side dedup key. Recipient scope prevents one
+    /// conversation's colliding message ID from suppressing another's drop,
+    /// while hashing keeps recipient keys out of the persisted snapshot.
+    private static func senderDropKey(
+        messageID: String,
+        recipientNoiseKey: Data
+    ) -> String {
+        var material = Data("bitchat-bridge-drop-dedup-v2".utf8)
+        appendLengthPrefixed(Data(messageID.utf8), to: &material)
+        appendLengthPrefixed(recipientNoiseKey, to: &material)
+        return "v2:\(material.sha256Hex())"
+    }
+
+    private static func appendLengthPrefixed(_ value: Data, to output: inout Data) {
+        let length = UInt32(value.count)
+        output.append(UInt8((length >> 24) & 0xFF))
+        output.append(UInt8((length >> 16) & 0xFF))
+        output.append(UInt8((length >> 8) & 0xFF))
+        output.append(UInt8(length & 0xFF))
+        output.append(value)
+    }
+
+    /// Previous releases persisted raw message IDs without recipient scope.
+    /// They remain conservative wildcards for their original 24-hour
+    /// lifetime: assigning one to a recipient would be guesswork and could
+    /// republish the original drop. New acceptances persist only v2 keys.
+    private func wasPublished(
+        legacyMessageID: String,
+        dedupKey: String,
+        now date: Date
+    ) -> Bool {
+        publishedDropKeys.contains(dedupKey, now: date)
+            || publishedDropKeys.contains(legacyMessageID, now: date)
+    }
+
     /// Parallel-deposit a sealed copy of an outbound private message as a
     /// relay drop. Called by the message router alongside physical courier
-    /// deposits; idempotent per message ID. Completion becomes true only
+    /// deposits; idempotent per recipient/message pair. Completion becomes
-    /// after a real relay acceptance arrives, which is when the router may
+    /// true only after a real relay acceptance arrives, which is when the
-    /// show "carried".
+    /// router may show "carried".
     func depositDrop(
         content: String,
         messageID: String,
@@ -229,9 +265,18 @@ final class BridgeCourierService: ObservableObject {
             completion(false)
             return
         }
-        guard !publishedDropKeys.contains(messageID, now: now()),
+        let date = now()
-              activeDropOperations[messageID] == nil,
+        let dedupKey = Self.senderDropKey(
-              !rejectedDropKeys.contains(messageID, now: now()) else {
+            messageID: messageID,
+            recipientNoiseKey: recipientNoiseKey
+        )
+        guard !wasPublished(
+            legacyMessageID: messageID,
+            dedupKey: dedupKey,
+            now: date
+        ),
+              activeDropOperations[dedupKey] == nil,
+              !rejectedDropKeys.contains(dedupKey, now: date) else {
             completion(false)
             return
         }
@@ -244,13 +289,13 @@ final class BridgeCourierService: ObservableObject {
         // of the sealing); suppress it in-memory so the retry sweep does not
         // churn, but never persist it as a published drop.
         guard let encoded = envelope.encode(), encoded.count <= Limits.maxDropEnvelopeBytes else {
-            rejectedDropKeys.insert(messageID, now: now())
+            rejectedDropKeys.insert(dedupKey, now: date)
             completion(false)
             return
         }
         let operationID = UUID()
-        activeDropOperations[messageID] = ActiveDropOperation(id: operationID, completion: completion)
+        activeDropOperations[dedupKey] = ActiveDropOperation(id: operationID, completion: completion)
-        publishDrop(envelope, messageID: messageID, operationID: operationID)
+        publishDrop(envelope, dedupKey: dedupKey, operationID: operationID)
     }
 
     /// Publishes held envelopes (mail we carry for others) as drops,
@@ -272,13 +317,14 @@ final class BridgeCourierService: ObservableObject {
         }
     }
 
-    /// Publishes a drop, or queues it when relays are down. `messageID` is the
+    /// Publishes a drop, or queues it when relays are down. `dedupKey` is the
-    /// sender-side dedup key (nil for held/relayed envelopes we don't track);
+    /// opaque sender-side recipient/message key (nil for held/relayed
-    /// it rides the pending queue so an evicted or failed drop can release its
+    /// envelopes we don't track); it rides the pending queue so an evicted or
-    /// in-flight slot. Completion reports actual NIP-01 relay acceptance.
+    /// failed drop can release its in-flight slot. Completion reports actual
+    /// NIP-01 relay acceptance.
     private func publishDrop(
         _ envelope: CourierEnvelope,
-        messageID: String? = nil,
+        dedupKey: String? = nil,
         operationID: UUID? = nil,
         untrackedCompletion: (@MainActor (Bool) -> Void)? = nil
     ) {
@@ -286,7 +332,7 @@ final class BridgeCourierService: ObservableObject {
               encoded.count <= Limits.maxDropEnvelopeBytes,
               !envelope.isExpired else {
             finishPublish(
-                messageID: messageID,
+                dedupKey: dedupKey,
                 operationID: operationID,
                 succeeded: false,
                 untrackedCompletion: untrackedCompletion
@@ -297,15 +343,15 @@ final class BridgeCourierService: ObservableObject {
             // Held mail remains in CourierStore and has no sender operation to
             // recover after an in-memory queue loss. Leave its cooldown unset
             // and let the next connected refresh offer it again.
-            guard messageID != nil else {
+            guard dedupKey != nil else {
                 untrackedCompletion?(false)
                 return
             }
-            pendingDrops.append((envelope, messageID, operationID))
+            pendingDrops.append((envelope, dedupKey, operationID))
             while pendingDrops.count > Limits.maxPendingDrops {
                 let evicted = pendingDrops.removeFirst()
                 finishPublish(
-                    messageID: evicted.dedupKey,
+                    dedupKey: evicted.dedupKey,
                     operationID: evicted.operationID,
                     succeeded: false
                 )
@@ -321,7 +367,7 @@ final class BridgeCourierService: ObservableObject {
               ) else {
             SecureLogger.error("📦🌉 Failed to compose courier drop", category: .encryption)
             finishPublish(
-                messageID: messageID,
+                dedupKey: dedupKey,
                 operationID: operationID,
                 succeeded: false,
                 untrackedCompletion: untrackedCompletion
@@ -331,7 +377,7 @@ final class BridgeCourierService: ObservableObject {
         guard let publishEvent else {
             SecureLogger.error("📦🌉 Courier drop publisher is not configured", category: .session)
             finishPublish(
-                messageID: messageID,
+                dedupKey: dedupKey,
                 operationID: operationID,
                 succeeded: false,
                 untrackedCompletion: untrackedCompletion
@@ -341,7 +387,7 @@ final class BridgeCourierService: ObservableObject {
         publishEvent(event) { [weak self] succeeded in
             guard let self else { return }
             guard self.finishPublish(
-                messageID: messageID,
+                dedupKey: dedupKey,
                 operationID: operationID,
                 succeeded: succeeded,
                 untrackedCompletion: untrackedCompletion
@@ -356,23 +402,23 @@ final class BridgeCourierService: ObservableObject {
 
     @discardableResult
     private func finishPublish(
-        messageID: String?,
+        dedupKey: String?,
         operationID: UUID?,
         succeeded: Bool,
         untrackedCompletion: (@MainActor (Bool) -> Void)? = nil
     ) -> Bool {
-        guard let messageID else {
+        guard let dedupKey else {
             untrackedCompletion?(succeeded)
             return true
         }
         // Missing/mismatched means this callback was duplicated, invalidated
         // by panic wipe, or belongs to an older attempt for the same key.
         guard let operationID,
-              let operation = activeDropOperations[messageID],
+              let operation = activeDropOperations[dedupKey],
               operation.id == operationID else { return false }
-        activeDropOperations.removeValue(forKey: messageID)
+        activeDropOperations.removeValue(forKey: dedupKey)
         if succeeded {
-            publishedDropKeys.insert(messageID, now: now())
+            publishedDropKeys.insert(dedupKey, now: now())
             persistDedup()
         }
         operation.completion(succeeded)
@@ -387,7 +433,7 @@ final class BridgeCourierService: ObservableObject {
         for item in queued {
             publishDrop(
                 item.envelope,
-                messageID: item.dedupKey,
+                dedupKey: item.dedupKey,
                 operationID: item.operationID
             )
         }

bitchat/Services/Gateway/BridgeDropDedupStore.swift

@@ -64,11 +64,11 @@ struct ExpiringIDSet {
 /// fresh drop (fresh throwaway seal, undeduplicatable downstream) and every
 /// gateway relaunch re-delivered the whole backlog. Field-verified: ~20
 /// copies of one DM delivered in 40ms fed the storm behind a permanent
-/// device freeze. Persisting both sides caps this at one drop per message
+/// device freeze. Persisting both sides caps this at one drop per
-/// ID per 24h regardless of relaunch count.
+/// recipient/message pair per 24h regardless of relaunch count.
 ///
-/// Contents are opaque IDs (message UUIDs, relay event IDs) — no plaintext,
+/// Contents are opaque hashes and relay event IDs — no plaintext or peer
-/// no peer identities — so until-first-unlock protection matches
+/// identities — so until-first-unlock protection matches
 /// `NostrProcessedEventStore`, and the file must load during a
 /// locked-background restoration relaunch. Wiped on panic with the rest of
 /// the courier state.

bitchat/Services/MessageRouter.swift

@@ -34,6 +34,20 @@ struct CourierDirectory {
 final class MessageRouter {
     typealias QueuedMessage = MessageOutboxStore.QueuedMessage
 
+    private struct PeerMessageKey: Hashable {
+        let peerID: PeerID
+        let messageID: String
+
+        static func == (lhs: PeerMessageKey, rhs: PeerMessageKey) -> Bool {
+            lhs.peerID == rhs.peerID && lhs.messageID == rhs.messageID
+        }
+
+        func hash(into hasher: inout Hasher) {
+            hasher.combine(peerID)
+            hasher.combine(messageID)
+        }
+    }
+
     private let transports: [Transport]
     private let now: () -> Date
     private let courierDirectory: CourierDirectory
@@ -104,15 +118,25 @@ final class MessageRouter {
     }
 
     private var bridgeSweepTask: Task<Void, Never>?
-    private var bridgeDepositsInFlight = Set<String>()
+    private var bridgeDepositsInFlight = Set<PeerMessageKey>()
 
     private var outbox: [PeerID: [QueuedMessage]] = [:]
+    /// Peer/message pairs whose latest router-owned transmission used an
+    /// already-established secure session and still await an ack. Peer scope
+    /// is required because message IDs are not globally unique across direct
+    /// conversations. This deliberately excludes messages handed to BLE while
+    /// a handshake is pending: BLE owns those sends and drains its queue after
+    /// authentication, so retrying them here would duplicate every normal
+    /// first-handshake DM.
+    private var secureTransmissions = Set<PeerMessageKey>()
 
     // Outbox limits to prevent unbounded memory growth
     private static let maxMessagesPerPeer = 100
     private static let messageTTLSeconds: TimeInterval = 24 * 60 * 60 // 24 hours
-    // Bound resends of messages sent on a weak reachability signal that never
+    // Bound actual sends that never receive an ack, whether they used weak
-    // get a delivery ack (e.g. peer on an old client that doesn't ack).
+    // reachability or an apparently secure session that keeps being replaced.
+    // Connected pre-handshake sends are transport-owned and do not burn this
+    // cap because BLE queues/drains them itself.
     private static let maxSendAttempts = 8
     // Redundant couriers improve delivery odds; receivers dedup by message ID.
     private static let maxCouriersPerMessage = 3
@@ -181,15 +205,28 @@ final class MessageRouter {
     // MARK: - Message Sending
 
     func sendPrivate(_ content: String, to peerID: PeerID, recipientNickname: String, messageID: String) {
+        let message = QueuedMessage(
+            content: content,
+            nickname: recipientNickname,
+            messageID: messageID,
+            timestamp: now(),
+            sendAttempts: 1
+        )
+
         if let transport = connectedTransport(for: peerID), transport.canDeliverSecurely(to: peerID) {
-            // A live link that can complete an encrypted delivery is a
+            // Even an established Noise session can be stale after the peer
-            // strong delivery signal; trust it outright.
+            // restarts or replaces its app. Persist before handing the packet
+            // to the transport so a fast ack cannot race ahead of retention,
+            // then keep the copy until a delivery/read ack clears it. A
+            // replacement handshake will retry this same message ID, which
+            // receivers deduplicate.
+            enqueue(message, for: peerID)
+            secureTransmissions.insert(PeerMessageKey(peerID: peerID, messageID: messageID))
             SecureLogger.debug("Routing PM via \(type(of: transport)) (connected) to \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
             transport.sendPrivateMessage(content, to: peerID, recipientNickname: recipientNickname, messageID: messageID)
             return
         }
 
-        let message = QueuedMessage(content: content, nickname: recipientNickname, messageID: messageID, timestamp: now(), sendAttempts: 1)
         if let transport = connectedTransport(for: peerID) {
             // "Connected" without an established secure session is forgeable:
             // link bindings heal on signature-verified "direct" announces, but
@@ -207,8 +244,9 @@ final class MessageRouter {
             // deposit is cleared on ack. Don't "optimize" the courier call
             // away.
             SecureLogger.debug("Routing PM via \(type(of: transport)) (connected, no secure session) to \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
-            transport.sendPrivateMessage(content, to: peerID, recipientNickname: recipientNickname, messageID: messageID)
             enqueue(message, for: peerID)
+            secureTransmissions.remove(PeerMessageKey(peerID: peerID, messageID: messageID))
+            transport.sendPrivateMessage(content, to: peerID, recipientNickname: recipientNickname, messageID: messageID)
             attemptCourierDeposit(messageID: messageID, for: peerID)
             return
         }
@@ -219,8 +257,8 @@ final class MessageRouter {
             // Send now, but retain a copy until a delivery/read ack clears it;
             // receivers dedup resends by message ID.
             SecureLogger.debug("Routing PM via \(type(of: transport)) (reachable) to \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
-            transport.sendPrivateMessage(content, to: peerID, recipientNickname: recipientNickname, messageID: messageID)
             enqueue(message, for: peerID)
+            transport.sendPrivateMessage(content, to: peerID, recipientNickname: recipientNickname, messageID: messageID)
             // "Reachable" without prompt delivery means the send only joined
             // a queue (Nostr with relays down): also hand a sealed copy to
             // any connected couriers rather than waiting for internet that
@@ -343,11 +381,12 @@ final class MessageRouter {
         for peerID: PeerID,
         recipientKey: Data
     ) {
+        let inFlightKey = PeerMessageKey(peerID: peerID, messageID: message.messageID)
         guard let bridgeCourierDeposit,
-              bridgeDepositsInFlight.insert(message.messageID).inserted else { return }
+              bridgeDepositsInFlight.insert(inFlightKey).inserted else { return }
         bridgeCourierDeposit(message.content, message.messageID, recipientKey) { [weak self] succeeded in
             guard let self else { return }
-            self.bridgeDepositsInFlight.remove(message.messageID)
+            self.bridgeDepositsInFlight.remove(inFlightKey)
             // A direct delivery may have cleared the outbox while the relay
             // relay confirmation was in flight; do not regress its UI state.
             guard succeeded, self.queuedMessage(message.messageID, for: peerID) != nil else { return }
@@ -366,15 +405,40 @@ final class MessageRouter {
 
     // MARK: - Outbox Management
 
-    /// A delivery or read ack confirms receipt; stop retaining the message.
+    /// A locally trusted delivery transition confirms receipt; stop retaining
+    /// every copy of the message. Authenticated remote receipts must use the
+    /// peer-bound overload below instead.
     func markDelivered(_ messageID: String) {
+        clearRetainedMessage(messageID, allowedPeerIDs: nil)
+    }
+
+    /// Stops retaining a message only for the authenticated conversation
+    /// aliases that produced the accepted receipt. A peer that learns another
+    /// conversation's message ID cannot use it to clear that conversation's
+    /// retry state.
+    func markDelivered(_ messageID: String, from peerIDs: Set<PeerID>) {
+        guard !peerIDs.isEmpty else { return }
+        _ = markDelivered(messageID, for: Array(peerIDs))
+    }
+
+    private func clearRetainedMessage(
+        _ messageID: String,
+        allowedPeerIDs: Set<PeerID>?
+    ) {
         var cleared = false
         for (peerID, queue) in outbox {
+            if let allowedPeerIDs, !allowedPeerIDs.contains(peerID) {
+                continue
+            }
             let filtered = queue.filter { $0.messageID != messageID }
             guard filtered.count != queue.count else { continue }
             outbox[peerID] = filtered.isEmpty ? nil : filtered
             cleared = true
         }
+        let matchingSecureTransmissions = secureTransmissions.filter {
+            $0.messageID == messageID
+        }
+        secureTransmissions.subtract(matchingSecureTransmissions)
         // The durable snapshot may still be hidden by protected data. Record
         // the ack even when this cold-load view cannot find the message, then
         // persist the current view so the store retains a removal tombstone.
@@ -385,6 +449,35 @@ final class MessageRouter {
         persistOutbox()
     }
 
+    /// A delivery or read ack authenticated to one account confirms receipt
+    /// only for that account's transport aliases. A colliding message ID
+    /// queued for another peer must remain retained.
+    @discardableResult
+    func markDelivered(_ messageID: String, for peerAliases: [PeerID]) -> Bool {
+        let peerIDs = Set(peerAliases)
+        guard !peerIDs.isEmpty else { return false }
+
+        var cleared = false
+        for peerID in peerIDs {
+            guard let queue = outbox[peerID] else { continue }
+            let filtered = queue.filter { $0.messageID != messageID }
+            guard filtered.count != queue.count else { continue }
+            outbox[peerID] = filtered.isEmpty ? nil : filtered
+            cleared = true
+        }
+        for peerID in peerIDs {
+            secureTransmissions.remove(PeerMessageKey(peerID: peerID, messageID: messageID))
+        }
+        // Preserve the scoped ack even when protected data hides the durable
+        // queue during a cold launch.
+        outboxStore?.recordRemoval(messageID: messageID, for: peerIDs)
+        if cleared {
+            metrics?.record(.outboxDelivered)
+        }
+        persistOutbox()
+        return cleared
+    }
+
     private func enqueue(_ message: QueuedMessage, for peerID: PeerID) {
         var message = message
         var queue = outbox[peerID] ?? []
@@ -408,7 +501,34 @@ final class MessageRouter {
         persistOutbox()
     }
 
+    @discardableResult
+    private func removeQueuedMessage(_ messageID: String, for peerID: PeerID) -> Bool {
+        guard let queue = outbox[peerID],
+              let index = queue.firstIndex(where: { $0.messageID == messageID }) else {
+            return false
+        }
+        var updated = queue
+        updated.remove(at: index)
+        outbox[peerID] = updated.isEmpty ? nil : updated
+        return true
+    }
+
+    @discardableResult
+    private func incrementSendAttemptsIfQueued(_ messageID: String, for peerID: PeerID) -> Bool {
+        guard var queue = outbox[peerID],
+              let index = queue.firstIndex(where: { $0.messageID == messageID }) else {
+            // A synchronous delivery/read ack may have cleared the retained
+            // copy while `sendPrivateMessage` was on the stack. Never
+            // resurrect it from the flush snapshot.
+            return false
+        }
+        queue[index].sendAttempts += 1
+        outbox[peerID] = queue
+        return true
+    }
+
     private func dropMessage(_ messageID: String, for peerID: PeerID) {
+        secureTransmissions.remove(PeerMessageKey(peerID: peerID, messageID: messageID))
         metrics?.record(.outboxDropped)
         onMessageDropped?(messageID, peerID)
     }
@@ -452,6 +572,7 @@ final class MessageRouter {
     /// Panic wipe: forget queued mail on disk and in memory.
     func wipeOutbox() {
         outbox.removeAll()
+        secureTransmissions.removeAll()
         outboxStore?.wipe()
     }
 
@@ -479,26 +600,160 @@ final class MessageRouter {
         }
     }
 
+    /// Retries only messages that the router previously transmitted through
+    /// an already-established secure session and that still await an ack.
+    ///
+    /// A peer restart can leave that local session looking usable until the
+    /// replacement handshake arrives; the first ciphertext is then
+    /// undecryptable remotely. Normal pre-handshake sends are intentionally
+    /// absent from `secureTransmissions` because BLE already queues
+    /// and drains them when authentication completes.
+    func retrySecurePrivateMessagesAfterAuthentication(for peerIDAliases: [PeerID]) {
+        typealias Candidate = (
+            peerID: PeerID,
+            message: QueuedMessage,
+            aliasOrder: Int,
+            queueOrder: Int
+        )
+
+        var visitedPeerIDs = Set<PeerID>()
+        var retriedMessageIDs = Set<String>()
+        var outboxChanged = false
+        let currentDate = now()
+        var candidates: [Candidate] = []
+
+        for (aliasOrder, peerID) in peerIDAliases.enumerated() {
+            guard visitedPeerIDs.insert(peerID).inserted else { continue }
+            guard let queued = outbox[peerID], !queued.isEmpty,
+                  let transport = connectedTransport(for: peerID),
+                  transport.canDeliverSecurely(to: peerID) else {
+                continue
+            }
+
+            for (queueOrder, message) in queued.enumerated() {
+                let key = PeerMessageKey(peerID: peerID, messageID: message.messageID)
+                guard secureTransmissions.contains(key) else { continue }
+                candidates.append((
+                    peerID: peerID,
+                    message: message,
+                    aliasOrder: aliasOrder,
+                    queueOrder: queueOrder
+                ))
+            }
+        }
+
+        // Conversation migration can leave retained messages split across the
+        // ephemeral and stable outbox keys. Merge both queues into one
+        // chronological stream so callback alias order cannot send newer mail
+        // ahead of older mail.
+        candidates.sort { lhs, rhs in
+            if lhs.message.timestamp != rhs.message.timestamp {
+                return lhs.message.timestamp < rhs.message.timestamp
+            }
+            if lhs.aliasOrder != rhs.aliasOrder {
+                return lhs.aliasOrder < rhs.aliasOrder
+            }
+            if lhs.queueOrder != rhs.queueOrder {
+                return lhs.queueOrder < rhs.queueOrder
+            }
+            return lhs.message.messageID < rhs.message.messageID
+        }
+
+        for candidate in candidates {
+            let peerID = candidate.peerID
+            let message = candidate.message
+            let key = PeerMessageKey(peerID: peerID, messageID: message.messageID)
+            guard retriedMessageIDs.insert(message.messageID).inserted,
+                  secureTransmissions.contains(key),
+                  queuedMessage(message.messageID, for: peerID) != nil,
+                  let transport = connectedTransport(for: peerID),
+                  transport.canDeliverSecurely(to: peerID) else {
+                continue
+            }
+
+            if currentDate.timeIntervalSince(message.timestamp) > Self.messageTTLSeconds {
+                if removeQueuedMessage(message.messageID, for: peerID) {
+                    dropMessage(message.messageID, for: peerID)
+                    outboxChanged = true
+                }
+                continue
+            }
+
+            guard message.sendAttempts < Self.maxSendAttempts else {
+                SecureLogger.warning(
+                    "📤 Dropping unacked PM for \(peerID.id.prefix(8))… id=\(message.messageID.prefix(8))… after \(message.sendAttempts) secure attempts",
+                    category: .session
+                )
+                if removeQueuedMessage(message.messageID, for: peerID) {
+                    dropMessage(message.messageID, for: peerID)
+                    outboxChanged = true
+                }
+                continue
+            }
+
+            SecureLogger.debug(
+                "Auth retry -> \(type(of: transport)) for \(peerID.id.prefix(8))… id=\(message.messageID.prefix(8))…",
+                category: .session
+            )
+            transport.sendPrivateMessage(
+                message.content,
+                to: peerID,
+                recipientNickname: message.nickname,
+                messageID: message.messageID
+            )
+            metrics?.record(.outboxResent)
+            outboxChanged = incrementSendAttemptsIfQueued(message.messageID, for: peerID) || outboxChanged
+        }
+
+        if outboxChanged {
+            persistOutbox()
+        }
+    }
+
     func flushOutbox(for peerID: PeerID) {
         guard let queued = outbox[peerID], !queued.isEmpty else { return }
         SecureLogger.debug("Flushing outbox for \(peerID.id.prefix(8))… count=\(queued.count)", category: .session)
 
         let now = now()
-        var remaining: [QueuedMessage] = []
+        var outboxChanged = false
 
         for message in queued {
+            // A synchronous ack from an earlier send in this flush may have
+            // removed an entry from the live outbox. The snapshot is only an
+            // iteration order; never use it to recreate removed messages.
+            guard queuedMessage(message.messageID, for: peerID) != nil else { continue }
+
             // Skip expired messages (TTL exceeded)
             if now.timeIntervalSince(message.timestamp) > Self.messageTTLSeconds {
                 SecureLogger.debug("⏰ Expired queued message for \(peerID.id.prefix(8))… id=\(message.messageID.prefix(8))… (age: \(Int(now.timeIntervalSince(message.timestamp)))s)", category: .session)
-                dropMessage(message.messageID, for: peerID)
+                if removeQueuedMessage(message.messageID, for: peerID) {
+                    dropMessage(message.messageID, for: peerID)
+                    outboxChanged = true
+                }
                 continue
             }
 
             if let transport = connectedTransport(for: peerID), transport.canDeliverSecurely(to: peerID) {
-                // Live link with a secure session: send and stop retaining.
+                // A secure session is meaningful enough to retry, but not
+                // proof that this particular ciphertext reached the peer: the
+                // remote app may have restarted while our old session still
+                // looked established. Retain until an ack, while bounding
+                // actual secure transmissions for peers that never ack.
+                guard message.sendAttempts < Self.maxSendAttempts else {
+                    SecureLogger.warning("📤 Dropping unacked PM for \(peerID.id.prefix(8))… id=\(message.messageID.prefix(8))… after \(message.sendAttempts) attempts", category: .session)
+                    if removeQueuedMessage(message.messageID, for: peerID) {
+                        dropMessage(message.messageID, for: peerID)
+                        outboxChanged = true
+                    }
+                    continue
+                }
                 SecureLogger.debug("Outbox -> \(type(of: transport)) (connected) for \(peerID.id.prefix(8))… id=\(message.messageID.prefix(8))…", category: .session)
+                secureTransmissions.insert(
+                    PeerMessageKey(peerID: peerID, messageID: message.messageID)
+                )
                 transport.sendPrivateMessage(message.content, to: peerID, recipientNickname: message.nickname, messageID: message.messageID)
                 metrics?.record(.outboxResent)
+                outboxChanged = incrementSendAttemptsIfQueued(message.messageID, for: peerID) || outboxChanged
             } else if let transport = connectedTransport(for: peerID) {
                 // "Connected" without a secure session — possibly a stolen
                 // binding from a replayed announce: send (a genuine link
@@ -511,9 +766,11 @@ final class MessageRouter {
                 // preserve. Retention stays bounded by the 24h outbox TTL
                 // and the per-peer FIFO cap.
                 SecureLogger.debug("Outbox -> \(type(of: transport)) (connected, no secure session) for \(peerID.id.prefix(8))… id=\(message.messageID.prefix(8))…", category: .session)
+                secureTransmissions.remove(
+                    PeerMessageKey(peerID: peerID, messageID: message.messageID)
+                )
                 transport.sendPrivateMessage(message.content, to: peerID, recipientNickname: message.nickname, messageID: message.messageID)
                 metrics?.record(.outboxResent)
-                remaining.append(message)
             } else if let transport = reachableTransport(for: peerID) {
                 // Reachability without a connection is a freshness heuristic,
                 // so the send can silently go nowhere: send but keep retaining
@@ -521,26 +778,22 @@ final class MessageRouter {
                 // that never ack.
                 guard message.sendAttempts < Self.maxSendAttempts else {
                     SecureLogger.warning("📤 Dropping unacked PM for \(peerID.id.prefix(8))… id=\(message.messageID.prefix(8))… after \(message.sendAttempts) attempts", category: .session)
-                    dropMessage(message.messageID, for: peerID)
+                    if removeQueuedMessage(message.messageID, for: peerID) {
+                        dropMessage(message.messageID, for: peerID)
+                        outboxChanged = true
+                    }
                     continue
                 }
                 SecureLogger.debug("Outbox -> \(type(of: transport)) (reachable) for \(peerID.id.prefix(8))… id=\(message.messageID.prefix(8))…", category: .session)
                 transport.sendPrivateMessage(message.content, to: peerID, recipientNickname: message.nickname, messageID: message.messageID)
                 metrics?.record(.outboxResent)
-                var retained = message
+                outboxChanged = incrementSendAttemptsIfQueued(message.messageID, for: peerID) || outboxChanged
-                retained.sendAttempts += 1
-                remaining.append(retained)
-            } else {
-                remaining.append(message)
             }
         }
 
-        if remaining.isEmpty {
+        if outboxChanged {
-            outbox.removeValue(forKey: peerID)
+            persistOutbox()
-        } else {
-            outbox[peerID] = remaining
         }
-        persistOutbox()
     }
 
     func flushAllOutbox() {

bitchat/Services/NoiseEncryptionService.swift

@@ -97,7 +97,7 @@ enum EncryptionStatus: Equatable {
     case noiseHandshaking   // Currently establishing
     case noiseSecured       // Established but not verified
     case noiseVerified      // Established and verified
-    
+
     var icon: String? {  // Made optional to hide icon when no handshake
         switch self {
         case .none:
@@ -660,7 +660,7 @@ final class NoiseEncryptionService {
         guard let packetData = packet.toBinaryDataForSigning() else {
             return nil
         }
-        
+
         // Sign with the noise private key (converted to Ed25519 for signing)
         guard let signature = signData(packetData) else {
             return nil
@@ -919,7 +919,7 @@ final class NoiseEncryptionService {
         }
         return try sessionManager.encrypt(data, for: peerID)
     }
-    
+
     /// Decrypt data from a specific peer
     func decrypt(_ data: Data, from peerID: PeerID) throws -> Data {
         try decryptWithSessionGeneration(data, from: peerID).plaintext
@@ -936,7 +936,7 @@ final class NoiseEncryptionService {
         let isStandardCiphertext = NoiseSecurityValidator.validateCiphertextSize(data)
         let isAdmittedCiphertext = isStandardCiphertext
             || NoiseSecurityValidator.validatePrivateFileCiphertextSize(data)
-        
+
         // A quarantined transport is deliberately unavailable for outbound
         // state, but remains receive-only until the responder proves identity
         // or the bounded rollback restores it.

bitchat/ViewModels/ChatDeliveryCoordinator.swift

@@ -21,6 +21,14 @@ protocol ChatDeliveryContext: AnyObject {
     /// message is unknown or no copy changed.
     @discardableResult
     func setDeliveryStatus(_ status: DeliveryStatus, forMessageID messageID: String) -> Bool
+    /// Applies an authenticated receipt only to the direct conversations
+    /// represented by the supplied peer aliases.
+    @discardableResult
+    func setDeliveryStatus(
+        _ status: DeliveryStatus,
+        forMessageID messageID: String,
+        inDirectPeerAliases peerIDs: Set<PeerID>
+    ) -> Bool
     /// Current delivery status of the message in whichever conversation holds it.
     func deliveryStatus(forMessageID messageID: String) -> DeliveryStatus?
     /// Message IDs across all direct conversations (read-receipt pruning).
@@ -33,6 +41,12 @@ protocol ChatDeliveryContext: AnyObject {
     func notifyUIChanged()
     /// Confirms receipt so the message router stops retaining the message for resend.
     func markMessageDelivered(_ messageID: String)
+    /// Peer-bound form for authenticated remote receipts. Only the supplied
+    /// conversation aliases may have retained state terminalized.
+    func markMessageDelivered(_ messageID: String, from peerIDs: Set<PeerID>)
+    /// Returns true only when `messageID` is one of our outgoing messages in
+    /// at least one of the authenticated peer's direct-conversation aliases.
+    func isOutgoingPrivateMessage(_ messageID: String, toAny peerIDs: Set<PeerID>) -> Bool
 }
 
 extension ChatViewModel: ChatDeliveryContext {
@@ -41,6 +55,19 @@ extension ChatViewModel: ChatDeliveryContext {
         conversations.setDeliveryStatus(status, forMessageID: messageID)
     }
 
+    @discardableResult
+    func setDeliveryStatus(
+        _ status: DeliveryStatus,
+        forMessageID messageID: String,
+        inDirectPeerAliases peerIDs: Set<PeerID>
+    ) -> Bool {
+        conversations.setDeliveryStatus(
+            status,
+            forMessageID: messageID,
+            inDirectPeerAliases: peerIDs
+        )
+    }
+
     func deliveryStatus(forMessageID messageID: String) -> DeliveryStatus? {
         conversations.deliveryStatus(forMessageID: messageID)
     }
@@ -59,6 +86,24 @@ extension ChatViewModel: ChatDeliveryContext {
             messageID: messageID
         )
     }
+
+    func markMessageDelivered(_ messageID: String, from peerIDs: Set<PeerID>) {
+        messageRouter.markDelivered(messageID, from: peerIDs)
+        // The caller has already bound this receipt to one of our outgoing
+        // conversations. Release the matching media retry only after that
+        // peer-scoped validation and accepted delivery-status transition.
+        mediaTransferCoordinator.confirmPrivateMediaDelivery(
+            messageID: messageID
+        )
+    }
+
+    func isOutgoingPrivateMessage(_ messageID: String, toAny peerIDs: Set<PeerID>) -> Bool {
+        peerIDs.contains { peerID in
+            privateMessages(for: peerID).contains { message in
+                message.id == messageID && message.senderPeerID == myPeerID
+            }
+        }
+    }
 }
 
 /// Thin mapper from delivery events (read receipts, transport delivery
@@ -86,9 +131,10 @@ final class ChatDeliveryCoordinator {
 
     @MainActor
     func didReceiveReadReceipt(_ receipt: ReadReceipt) {
-        updateMessageDeliveryStatus(
+        updateAcknowledgedMessageDeliveryStatus(
             receipt.originalMessageID,
-            status: .read(by: receipt.readerNickname, at: receipt.timestamp)
+            status: .read(by: receipt.readerNickname, at: receipt.timestamp),
+            from: [receipt.readerID]
         )
     }
 
@@ -105,17 +151,47 @@ final class ChatDeliveryCoordinator {
     @MainActor
     @discardableResult
     func updateMessageDeliveryStatus(_ messageID: String, status: DeliveryStatus) -> Bool {
+        guard context.setDeliveryStatus(status, forMessageID: messageID) else {
+            return false
+        }
         switch status {
         case .delivered, .read:
-            // Confirmed receipt — stop retaining the message for resend.
+            // Terminalize only after the store accepted the transition.
             context.markMessageDelivered(messageID)
         default:
             break
         }
+        context.notifyUIChanged()
+        return true
+    }
 
-        guard context.setDeliveryStatus(status, forMessageID: messageID) else {
+    /// Applies an authenticated remote delivery/read receipt only when it
+    /// belongs to one of our outgoing messages in that peer's conversation.
+    /// Retry state is cleared after, never before, the status transition is
+    /// accepted by the store.
+    @MainActor
+    @discardableResult
+    func updateAcknowledgedMessageDeliveryStatus(
+        _ messageID: String,
+        status: DeliveryStatus,
+        from peerIDAliases: Set<PeerID>
+    ) -> Bool {
+        switch status {
+        case .delivered, .read:
+            break
+        default:
             return false
         }
+        guard !peerIDAliases.isEmpty,
+              context.isOutgoingPrivateMessage(messageID, toAny: peerIDAliases),
+              context.setDeliveryStatus(
+                status,
+                forMessageID: messageID,
+                inDirectPeerAliases: peerIDAliases
+              ) else {
+            return false
+        }
+        context.markMessageDelivered(messageID, from: peerIDAliases)
         context.notifyUIChanged()
         return true
     }

bitchat/ViewModels/ChatPrivateConversationCoordinator.swift

@@ -85,6 +85,11 @@ protocol ChatPrivateConversationContext: AnyObject {
     func routePrivateMessage(_ content: String, to peerID: PeerID, recipientNickname: String, messageID: String)
     @discardableResult
     func routeReadReceipt(_ receipt: ReadReceipt, to peerID: PeerID) -> Bool
+    /// Confirms an authenticated delivery/read acknowledgement so the router
+    /// stops retaining the original private message for resend. The peer
+    /// aliases scope the removal to the authenticated sender.
+    @discardableResult
+    func markMessageDelivered(_ messageID: String, for peerIDs: [PeerID]) -> Bool
     func sendMeshReadReceipt(_ receipt: ReadReceipt, to peerID: PeerID)
     @discardableResult
     func sendGeohashPrivateMessage(
@@ -172,6 +177,11 @@ extension ChatViewModel: ChatPrivateConversationContext {
         messageRouter.sendReadReceipt(receipt, to: peerID)
     }
 
+    @discardableResult
+    func markMessageDelivered(_ messageID: String, for peerIDs: [PeerID]) -> Bool {
+        messageRouter.markDelivered(messageID, for: peerIDs)
+    }
+
     func routeFavoriteNotification(to peerID: PeerID, isFavorite: Bool) {
         messageRouter.sendFavoriteNotification(to: peerID, isFavorite: isFavorite)
     }
@@ -269,6 +279,60 @@ final class ChatPrivateConversationCoordinator {
         return true
     }
 
+    /// Account DMs can arrive under the authenticated peer's full Noise key
+    /// while an existing mesh conversation is keyed by its derived short ID.
+    /// These are the only aliases we may safely join: the short ID is derived
+    /// directly from the authenticated key, rather than guessed from a
+    /// nickname or found by scanning unrelated chats.
+    private func accountConversationAliases(for peerID: PeerID) -> [PeerID] {
+        guard peerID.noiseKey != nil else { return [peerID] }
+        let shortPeerID = peerID.toShort()
+        return shortPeerID == peerID ? [peerID] : [peerID, shortPeerID]
+    }
+
+    /// Keeps a connected account DM on its short routing ID and an offline DM
+    /// on its stable Noise-key ID, folding the other authenticated alias into
+    /// it and handing an open sheet across without closing it.
+    private func consolidateAccountConversationAliases(for peerID: PeerID) -> PeerID {
+        let aliases = accountConversationAliases(for: peerID)
+        guard aliases.count > 1 else { return peerID }
+
+        let shortPeerID = peerID.toShort()
+        let targetPeerID = context.isPeerConnected(shortPeerID) ? shortPeerID : peerID
+        let sourcePeerIDs = aliases.filter { $0 != targetPeerID }
+
+        for sourcePeerID in sourcePeerIDs where !context.privateMessages(for: sourcePeerID).isEmpty {
+            context.migratePrivateChat(from: sourcePeerID, to: targetPeerID)
+            // ConversationStore deliberately preserves message values during a
+            // generic migration, including its destination-wins rule for
+            // duplicate IDs. Rewrite the resulting canonical copies so later
+            // read-receipt scans compare against the new routing key without
+            // replacing a newer destination value with the source snapshot.
+            let canonicalMessages = context.privateMessages(for: targetPeerID)
+            for message in canonicalMessages where message.senderPeerID == sourcePeerID {
+                context.upsertPrivateMessage(
+                    BitchatMessage(
+                        id: message.id,
+                        sender: message.sender,
+                        content: message.content,
+                        timestamp: message.timestamp,
+                        isRelay: message.isRelay,
+                        originalSender: message.originalSender,
+                        isPrivate: message.isPrivate,
+                        recipientNickname: message.recipientNickname,
+                        senderPeerID: targetPeerID,
+                        mentions: message.mentions,
+                        deliveryStatus: message.deliveryStatus,
+                        isBridged: message.isBridged
+                    ),
+                    in: targetPeerID
+                )
+            }
+        }
+        context.handOffSelectedPrivateChat(from: sourcePeerIDs, to: targetPeerID)
+        return targetPeerID
+    }
+
     func sendPrivateMessage(_ content: String, to peerID: PeerID) {
         guard !content.isEmpty else { return }
 
@@ -491,6 +555,8 @@ final class ChatPrivateConversationCoordinator {
             return
         }
 
+        let conversationPeerID = consolidateAccountConversationAliases(for: convKey)
+
         if context.privateChatsContainMessage(withID: messageId) { return }
 
         let message = BitchatMessage(
@@ -501,18 +567,18 @@ final class ChatPrivateConversationCoordinator {
             isRelay: false,
             isPrivate: true,
             recipientNickname: context.nickname,
-            senderPeerID: convKey,
+            senderPeerID: conversationPeerID,
             deliveryStatus: .delivered(to: context.nickname, at: Date())
         )
 
-        context.appendPrivateMessage(message, to: convKey)
+        context.appendPrivateMessage(message, to: conversationPeerID)
 
-        let isViewing = context.selectedPrivateChatPeer == convKey
+        let isViewing = context.selectedPrivateChatPeer == conversationPeerID
         let wasReadBefore = context.sentReadReceipts.contains(messageId)
         let isRecentMessage = Date().timeIntervalSince(messageTimestamp) < 30
         let shouldMarkUnread = !wasReadBefore && !isViewing && isRecentMessage
         if shouldMarkUnread {
-            context.markPrivateChatUnread(convKey)
+            context.markPrivateChatUnread(conversationPeerID)
         }
 
         if isViewing {
@@ -520,7 +586,7 @@ final class ChatPrivateConversationCoordinator {
         }
 
         if !isViewing && shouldMarkUnread {
-            context.notifyPrivateMessage(from: senderName, message: pm.content, peerID: convKey)
+            context.notifyPrivateMessage(from: senderName, message: pm.content, peerID: conversationPeerID)
         }
 
         context.notifyUIChanged()
@@ -529,17 +595,32 @@ final class ChatPrivateConversationCoordinator {
     func handleDelivered(_ payload: NoisePayload, senderPubkey: String, convKey: PeerID) {
         guard let messageID = String(data: payload.data, encoding: .utf8) else { return }
 
-        if context.privateChat(convKey, containsMessageWithID: messageID) {
+        let aliases = accountConversationAliases(for: convKey)
-            context.setPrivateDeliveryStatus(
+        let clearedRetainedMessage = convKey.noiseKey != nil
+            ? context.markMessageDelivered(messageID, for: aliases)
+            : false
+        let hasConversationMessage = aliases.contains {
+            context.privateChat($0, containsMessageWithID: messageID)
+        }
+        if hasConversationMessage {
+            let conversationPeerID = consolidateAccountConversationAliases(for: convKey)
+            let didChange = context.setPrivateDeliveryStatus(
                 .delivered(to: context.displayNameForNostrPubkey(senderPubkey), at: Date()),
                 forMessageID: messageID,
-                peerID: convKey
+                peerID: conversationPeerID
             )
-            context.notifyUIChanged()
+            if didChange {
+                context.notifyUIChanged()
+            }
             SecureLogger.info(
                 "GeoDM: recv DELIVERED for mid=\(messageID.prefix(8))… from=\(senderPubkey.prefix(8))…",
                 category: .session
             )
+        } else if clearedRetainedMessage {
+            SecureLogger.debug(
+                "GeoDM: recv DELIVERED for cleared mid=\(messageID.prefix(8))… from=\(senderPubkey.prefix(8))…",
+                category: .session
+            )
         } else {
             // A stale ack for a message this device no longer tracks (dropped
             // outbox entry, cleared chat, or a peer re-acking after losing our
@@ -551,14 +632,29 @@ final class ChatPrivateConversationCoordinator {
     func handleReadReceipt(_ payload: NoisePayload, senderPubkey: String, convKey: PeerID) {
         guard let messageID = String(data: payload.data, encoding: .utf8) else { return }
 
-        if context.privateChat(convKey, containsMessageWithID: messageID) {
+        let aliases = accountConversationAliases(for: convKey)
-            context.setPrivateDeliveryStatus(
+        let clearedRetainedMessage = convKey.noiseKey != nil
+            ? context.markMessageDelivered(messageID, for: aliases)
+            : false
+        let hasConversationMessage = aliases.contains {
+            context.privateChat($0, containsMessageWithID: messageID)
+        }
+        if hasConversationMessage {
+            let conversationPeerID = consolidateAccountConversationAliases(for: convKey)
+            let didChange = context.setPrivateDeliveryStatus(
                 .read(by: context.displayNameForNostrPubkey(senderPubkey), at: Date()),
                 forMessageID: messageID,
-                peerID: convKey
+                peerID: conversationPeerID
             )
-            context.notifyUIChanged()
+            if didChange {
+                context.notifyUIChanged()
+            }
             SecureLogger.info("GeoDM: recv READ for mid=\(messageID.prefix(8))… from=\(senderPubkey.prefix(8))…", category: .session)
+        } else if clearedRetainedMessage {
+            SecureLogger.debug(
+                "GeoDM: recv READ for cleared mid=\(messageID.prefix(8))… from=\(senderPubkey.prefix(8))…",
+                category: .session
+            )
         } else {
             SecureLogger.warning("GeoDM: read ack for unknown mid=\(messageID.prefix(8))… conv=\(convKey)", category: .session)
         }

bitchat/ViewModels/ChatTransportEventCoordinator.swift

@@ -62,10 +62,15 @@ protocol ChatTransportEventContext: AnyObject {
     func sendMeshDeliveryAck(for messageID: String, to peerID: PeerID)
 
     // MARK: Delivery status
-    /// Applies the status to every known location of the message.
+    /// Applies an authenticated receipt to the message only when it belongs
-    /// Returns `false` when no message with that ID was updated.
+    /// to the supplied peer conversation aliases. Returns `false` for an
+    /// unknown ID, wrong peer, or rejected status transition.
     @discardableResult
-    func applyMessageDeliveryStatus(_ messageID: String, status: DeliveryStatus) -> Bool
+    func applyAcknowledgedMessageDeliveryStatus(
+        _ messageID: String,
+        status: DeliveryStatus,
+        from peerIDAliases: Set<PeerID>
+    ) -> Bool
     func deliveryStatus(for messageID: String) -> DeliveryStatus?
 
     // MARK: Verification payloads
@@ -122,8 +127,16 @@ extension ChatViewModel: ChatTransportEventContext {
     }
 
     @discardableResult
-    func applyMessageDeliveryStatus(_ messageID: String, status: DeliveryStatus) -> Bool {
+    func applyAcknowledgedMessageDeliveryStatus(
-        deliveryCoordinator.updateMessageDeliveryStatus(messageID, status: status)
+        _ messageID: String,
+        status: DeliveryStatus,
+        from peerIDAliases: Set<PeerID>
+    ) -> Bool {
+        deliveryCoordinator.updateAcknowledgedMessageDeliveryStatus(
+            messageID,
+            status: status,
+            from: peerIDAliases
+        )
     }
 
     func deliveryStatus(for messageID: String) -> DeliveryStatus? {
@@ -446,9 +459,10 @@ private extension ChatTransportEventCoordinator {
             guard let messageID = String(data: payload, encoding: .utf8) else { return }
 
             let name = deliveryStatusName(for: peerID, in: context)
-            let didUpdate = context.applyMessageDeliveryStatus(
+            let didUpdate = context.applyAcknowledgedMessageDeliveryStatus(
                 messageID,
-                status: .delivered(to: name, at: Date())
+                status: .delivered(to: name, at: Date()),
+                from: receiptPeerAliases(for: peerID, in: context)
             )
 
             if !didUpdate {
@@ -463,9 +477,10 @@ private extension ChatTransportEventCoordinator {
             guard let messageID = String(data: payload, encoding: .utf8) else { return }
 
             let name = deliveryStatusName(for: peerID, in: context)
-            let didUpdate = context.applyMessageDeliveryStatus(
+            let didUpdate = context.applyAcknowledgedMessageDeliveryStatus(
                 messageID,
-                status: .read(by: name, at: Date())
+                status: .read(by: name, at: Date()),
+                from: receiptPeerAliases(for: peerID, in: context)
             )
 
             if !didUpdate {
@@ -503,4 +518,21 @@ private extension ChatTransportEventCoordinator {
     func deliveryStatusName(for peerID: PeerID, in context: any ChatTransportEventContext) -> String {
         context.unifiedPeer(for: peerID)?.nickname ?? context.resolveNickname(for: peerID)
     }
+
+    @MainActor
+    func receiptPeerAliases(
+        for peerID: PeerID,
+        in context: any ChatTransportEventContext
+    ) -> Set<PeerID> {
+        var aliases: Set<PeerID> = [peerID]
+        // The active authenticated Noise key is authoritative. A cached
+        // ephemeral→stable mapping can predate an identity replacement, so
+        // use it only when the live session cannot provide its static key.
+        if let keyData = context.noiseSessionPublicKeyData(for: peerID) {
+            aliases.insert(PeerID(hexData: keyData))
+        } else if let stablePeerID = context.cachedStablePeerID(for: peerID) {
+            aliases.insert(stablePeerID)
+        }
+        return aliases
+    }
 }

bitchat/ViewModels/ChatVerificationCoordinator.swift

@@ -59,6 +59,10 @@ protocol ChatVerificationContext: AnyObject {
     func hasEstablishedNoiseSession(with peerID: PeerID) -> Bool
     func triggerHandshake(with peerID: PeerID)
     func privateMediaPeerDidAuthenticate(_ peerID: PeerID)
+    /// Retries only private messages previously transmitted through a secure
+    /// session and still pending an ack. Both ephemeral and stable aliases
+    /// are supplied because either can own the outbox entry.
+    func retrySecurePrivateMessagesAfterAuthentication(for peerIDAliases: [PeerID])
     func sendVerifyChallenge(to peerID: PeerID, noiseKeyHex: String, nonceA: Data)
     func sendVerifyResponse(to peerID: PeerID, noiseKeyHex: String, nonceA: Data)
 
@@ -121,6 +125,10 @@ extension ChatViewModel: ChatVerificationContext {
         mediaTransferCoordinator.peerDidAuthenticate(peerID.toShort())
     }
 
+    func retrySecurePrivateMessagesAfterAuthentication(for peerIDAliases: [PeerID]) {
+        messageRouter.retrySecurePrivateMessagesAfterAuthentication(for: peerIDAliases)
+    }
+
     func sendVerifyChallenge(to peerID: PeerID, noiseKeyHex: String, nonceA: Data) {
         meshService.sendVerifyChallenge(to: peerID, noiseKeyHex: noiseKeyHex, nonceA: nonceA)
     }
@@ -216,16 +224,37 @@ final class ChatVerificationCoordinator {
 
                     self.context.invalidateEncryptionCache(for: peerID)
 
-                    if self.context.cachedStablePeerID(for: peerID) == nil,
+                    var authenticatedStablePeerID: PeerID?
-                       let keyData = self.context.noiseSessionPublicKeyData(for: peerID) {
+                    if let keyData = self.context.noiseSessionPublicKeyData(for: peerID) {
                         let stablePeerID = PeerID(hexData: keyData)
-                        self.context.cacheStablePeerID(stablePeerID, for: peerID)
+                        authenticatedStablePeerID = stablePeerID
+                        if self.context.cachedStablePeerID(for: peerID) != stablePeerID {
+                            // The freshly authenticated Noise key outranks a
+                            // stale announce-derived alias.
+                            self.context.cacheStablePeerID(stablePeerID, for: peerID)
+                        }
                         SecureLogger.debug(
                             "🗺️ Mapped short peerID to Noise key for header continuity: \(peerID) -> \(stablePeerID.id.prefix(8))…",
                             category: .session
                         )
                     }
 
+                    // A locally established session may have belonged to the
+                    // peer's previous app process. The first ciphertext sent
+                    // into that stale session is retained by MessageRouter;
+                    // retry it now that this newly authenticated/replacement
+                    // session can actually decrypt it.
+                    var peerIDAliases = [peerID]
+                    if let stablePeerID = authenticatedStablePeerID
+                        ?? self.context.cachedStablePeerID(for: peerID),
+                       stablePeerID != peerID {
+                        // Conversations can migrate from the ephemeral BLE ID
+                        // to the authenticated Noise-key ID. Retry both aliases
+                        // because either may own the retained outbox entry.
+                        peerIDAliases.append(stablePeerID)
+                    }
+                    self.context.retrySecurePrivateMessagesAfterAuthentication(for: peerIDAliases)
+
                     if var pending = self.pendingQRVerifications[peerID], pending.sent == false {
                         self.context.sendVerifyChallenge(
                             to: peerID,

bitchat/Views/ContentSheetViews.swift

@@ -6,11 +6,26 @@ import UIKit
 import AppKit
 #endif
 
+struct ContentPeopleSheetModalPresentationState {
+    var isImagePreviewPresented = false
+    var isVerificationSheetPresented = false
+    var legacyPrivateMediaConsentRequest: LegacyPrivateMediaConsentRequest? = nil
+    var isMediaPickerPresented = false
+
+    var hasPresentation: Bool {
+        isImagePreviewPresented
+            || isVerificationSheetPresented
+            || legacyPrivateMediaConsentRequest != nil
+            || isMediaPickerPresented
+    }
+}
+
 struct ContentPeopleSheetView: View {
     @EnvironmentObject private var appChromeModel: AppChromeModel
     @EnvironmentObject private var privateConversationModel: PrivateConversationModel
     @EnvironmentObject private var verificationModel: VerificationModel
     @EnvironmentObject private var conversationUIModel: ConversationUIModel
+    @Environment(\.scenePhase) private var scenePhase
 
     @Binding var showSidebar: Bool
     @Binding var messageText: String
@@ -23,6 +38,7 @@ struct ContentPeopleSheetView: View {
     var isTextFieldFocused: FocusState<Bool>.Binding
     @ObservedObject var voiceRecordingVM: VoiceRecordingViewModel
     @Binding var autocompleteDebounceTimer: Timer?
+    @State private var showVerifySheet = false
     @ThemedPalette private var palette
 
     let headerHeight: CGFloat
@@ -35,6 +51,40 @@ struct ContentPeopleSheetView: View {
     @Binding var showMacImagePicker: Bool
     #endif
 
+    private var hasModalPresentation: Bool {
+        #if os(iOS)
+        let isMediaPickerPresented = showImagePicker
+        #else
+        let isMediaPickerPresented = showMacImagePicker
+        #endif
+
+        return ContentPeopleSheetModalPresentationState(
+            isImagePreviewPresented: imagePreviewURL != nil,
+            isVerificationSheetPresented: showVerifySheet,
+            legacyPrivateMediaConsentRequest:
+                conversationUIModel.legacyPrivateMediaConsentRequest,
+            isMediaPickerPresented: isMediaPickerPresented
+        ).hasPresentation
+    }
+
+    private var bluetoothAlertBinding: Binding<Bool> {
+        Binding(
+            get: {
+                scenePhase == .active
+                    && appChromeModel.showBluetoothAlert
+                    && !hasModalPresentation
+            },
+            set: { isPresented in
+                guard !isPresented,
+                      scenePhase == .active,
+                      !hasModalPresentation else {
+                    return
+                }
+                appChromeModel.showBluetoothAlert = false
+            }
+        )
+    }
+
     var body: some View {
         let legacyConsentRequest = conversationUIModel.legacyPrivateMediaConsentRequest
         NavigationStack {
@@ -78,7 +128,8 @@ struct ContentPeopleSheetView: View {
                     #endif
                 } else {
                     ContentPeopleListView(
-                        showSidebar: $showSidebar
+                        showSidebar: $showSidebar,
+                        showVerifySheet: $showVerifySheet
                     )
                 }
             }
@@ -182,6 +233,17 @@ struct ContentPeopleSheetView: View {
             }
         }
         #endif
+        .alert(
+            "content.alert.bluetooth_required.title",
+            isPresented: bluetoothAlertBinding
+        ) {
+            Button("content.alert.bluetooth_required.settings") {
+                SystemSettings.bluetooth.open()
+            }
+            Button("common.ok", role: .cancel) {}
+        } message: {
+            Text(appChromeModel.bluetoothAlertMessage)
+        }
     }
 }
 
@@ -196,8 +258,7 @@ private struct ContentPeopleListView: View {
     @ThemedPalette private var palette
 
     @Binding var showSidebar: Bool
-
+    @Binding var showVerifySheet: Bool
-    @State private var showVerifySheet = false
 
     var body: some View {
         VStack(spacing: 0) {

bitchat/Views/ContentView.swift

@@ -14,6 +14,61 @@ import AppKit
 #endif
 import BitFoundation
 
+struct ContentRootModalPresentationState {
+    var isPeopleSheetPresented = false
+    var isAppInfoPresented = false
+    var isFingerprintPresented = false
+    var isLocationChannelsSheetPresented = false
+    var isNoticesSheetPresented = false
+    var isImagePreviewPresented = false
+    var isVerificationSheetPresented = false
+    var isVoiceAlertPresented = false
+    var isScreenshotPrivacyAlertPresented = false
+    var isMediaPickerPresented = false
+
+    var hasPresentation: Bool {
+        isPeopleSheetPresented
+            || isAppInfoPresented
+            || isFingerprintPresented
+            || isLocationChannelsSheetPresented
+            || isNoticesSheetPresented
+            || isImagePreviewPresented
+            || isVerificationSheetPresented
+            || isVoiceAlertPresented
+            || isScreenshotPrivacyAlertPresented
+            || isMediaPickerPresented
+    }
+}
+
+extension ContentRootModalPresentationState {
+    @MainActor
+    init(
+        appChromeModel: AppChromeModel,
+        isPeopleSheetPresented: Bool = false,
+        isImagePreviewPresented: Bool = false,
+        isVerificationSheetPresented: Bool = false,
+        isVoiceAlertPresented: Bool = false,
+        isMediaPickerPresented: Bool = false
+    ) {
+        self.init(
+            isPeopleSheetPresented: isPeopleSheetPresented,
+            isAppInfoPresented: appChromeModel.isAppInfoPresented,
+            isFingerprintPresented:
+                appChromeModel.showingFingerprintFor != nil,
+            isLocationChannelsSheetPresented:
+                appChromeModel.isLocationChannelsSheetPresented,
+            isNoticesSheetPresented:
+                appChromeModel.isNoticesSheetPresented,
+            isImagePreviewPresented: isImagePreviewPresented,
+            isVerificationSheetPresented: isVerificationSheetPresented,
+            isVoiceAlertPresented: isVoiceAlertPresented,
+            isScreenshotPrivacyAlertPresented:
+                appChromeModel.showScreenshotPrivacyWarning,
+            isMediaPickerPresented: isMediaPickerPresented
+        )
+    }
+}
+
 /// On macOS 14+, disables the default system focus ring on TextFields.
 /// On earlier macOS versions and on iOS this is a no-op.
 struct FocusEffectDisabledModifier: ViewModifier {
@@ -42,6 +97,7 @@ struct ContentView: View {
     @FocusState private var isTextFieldFocused: Bool
     @Environment(\.colorScheme) var colorScheme
     @Environment(\.appTheme) private var appTheme
+    @Environment(\.scenePhase) private var scenePhase
     @State private var showSidebar = false
     @State private var selectedMessageSender: String?
     @State private var selectedMessageSenderID: PeerID?
@@ -71,6 +127,45 @@ struct ContentView: View {
 
     private var usesGlassLayout: Bool { appTheme.usesGlassChrome }
 
+    private var isPeopleSheetPresented: Bool {
+        showSidebar || selectedPrivatePeerID != nil
+    }
+
+    private var hasRootModalPresentation: Bool {
+        #if os(iOS)
+        let isMediaPickerPresented = showImagePicker
+        #else
+        let isMediaPickerPresented = showMacImagePicker
+        #endif
+
+        return ContentRootModalPresentationState(
+            appChromeModel: appChromeModel,
+            isPeopleSheetPresented: isPeopleSheetPresented,
+            isImagePreviewPresented: imagePreviewURL != nil,
+            isVerificationSheetPresented: showVerifySheet,
+            isVoiceAlertPresented: voiceRecordingVM.showAlert,
+            isMediaPickerPresented: isMediaPickerPresented
+        ).hasPresentation
+    }
+
+    private var rootBluetoothAlertBinding: Binding<Bool> {
+        Binding(
+            get: {
+                scenePhase == .active
+                    && appChromeModel.showBluetoothAlert
+                    && !hasRootModalPresentation
+            },
+            set: { isPresented in
+                guard !isPresented,
+                      scenePhase == .active,
+                      !hasRootModalPresentation else {
+                    return
+                }
+                appChromeModel.showBluetoothAlert = false
+            }
+        )
+    }
+
     var body: some View {
         mainContent
             .onAppear {
@@ -107,11 +202,18 @@ struct ContentView: View {
         }
         .sheet(
             isPresented: Binding(
-                get: { showSidebar || selectedPrivatePeerID != nil },
+                get: { isPeopleSheetPresented },
                 set: { isPresented in
                     if !isPresented {
                         showSidebar = false
-                        privateConversationModel.endConversation()
+                        // Scene/background and Bluetooth-alert presentation
+                        // reconciliation are not user requests to leave the
+                        // conversation. Keep the selected DM so the sheet
+                        // remains live when the app returns from Settings.
+                        if scenePhase == .active,
+                           !appChromeModel.showBluetoothAlert {
+                            privateConversationModel.endConversation()
+                        }
                     }
                 }
             )
@@ -222,7 +324,7 @@ struct ContentView: View {
         }, message: {
             Text(voiceRecordingVM.state.alertMessage)
         })
-        .alert("content.alert.bluetooth_required.title", isPresented: $appChromeModel.showBluetoothAlert) {
+        .alert("content.alert.bluetooth_required.title", isPresented: rootBluetoothAlertBinding) {
             Button("content.alert.bluetooth_required.settings") {
                 SystemSettings.bluetooth.open()
             }

bitchatTests/ChatPrivateConversationCoordinatorContextTests.swift

@@ -177,6 +177,9 @@ private final class MockChatPrivateConversationContext: ChatPrivateConversationC
     private(set) var geoDeliveryAcks: [(messageID: String, recipientHex: String)] = []
     private(set) var geoReadReceipts: [(messageID: String, recipientHex: String)] = []
     var geohashPrivateMessageAccepted = true
+    var queuedMessageIDsByPeerID: [PeerID: Set<String>] = [:]
+    private(set) var deliveryAckAttempts: [(messageID: String, peerIDs: [PeerID])] = []
+    private(set) var deliveredMessageIDs: [String] = []
 
     func routePrivateMessage(_ content: String, to peerID: PeerID, recipientNickname: String, messageID: String) {
         routedPrivateMessages.append((content, peerID, messageID))
@@ -188,6 +191,22 @@ private final class MockChatPrivateConversationContext: ChatPrivateConversationC
         return routeReadReceiptResult
     }
 
+    @discardableResult
+    func markMessageDelivered(_ messageID: String, for peerIDs: [PeerID]) -> Bool {
+        deliveryAckAttempts.append((messageID, peerIDs))
+        var cleared = false
+        for peerID in Set(peerIDs) {
+            guard var queued = queuedMessageIDsByPeerID[peerID],
+                  queued.remove(messageID) != nil else { continue }
+            queuedMessageIDsByPeerID[peerID] = queued.isEmpty ? nil : queued
+            cleared = true
+        }
+        if cleared {
+            deliveredMessageIDs.append(messageID)
+        }
+        return cleared
+    }
+
     func sendMeshReadReceipt(_ receipt: ReadReceipt, to peerID: PeerID) {
         meshReadReceipts.append((receipt.originalMessageID, peerID))
     }
@@ -382,6 +401,66 @@ struct ChatPrivateConversationCoordinatorContextTests {
             convKey: convKey
         )
         #expect(context.notifyUIChangedCount == 2)
+        #expect(context.deliveryAckAttempts.isEmpty)
+        #expect(context.deliveredMessageIDs.isEmpty)
+    }
+
+    @Test @MainActor
+    func accountDMAcks_findShortIDMessageAndHandConversationToStable() async {
+        let context = MockChatPrivateConversationContext()
+        let coordinator = ChatPrivateConversationCoordinator(context: context)
+        let noiseKey = Data(repeating: 0xD5, count: 32)
+        let stablePeerID = PeerID(hexData: noiseKey)
+        let shortPeerID = stablePeerID.toShort()
+        let senderPubkey = "feedface00112233"
+        context.displayNamesByPubkey[senderPubkey] = "alice"
+        context.selectedPrivateChatPeer = shortPeerID
+        context.privateChats[shortPeerID] = [
+            makeIncomingMessage(id: "mine-short-1", sender: "me"),
+            makeIncomingMessage(id: "mine-short-2", sender: "me")
+        ]
+        context.queuedMessageIDsByPeerID[shortPeerID] = ["mine-short-1", "mine-short-2"]
+
+        coordinator.handleDelivered(
+            NoisePayload(type: .delivered, data: Data("mine-short-1".utf8)),
+            senderPubkey: senderPubkey,
+            convKey: stablePeerID
+        )
+        coordinator.handleReadReceipt(
+            NoisePayload(type: .readReceipt, data: Data("mine-short-2".utf8)),
+            senderPubkey: senderPubkey,
+            convKey: stablePeerID
+        )
+
+        #expect(context.privateChats[shortPeerID] == nil)
+        #expect(isDelivered(context.privateChats[stablePeerID]?.first?.deliveryStatus, to: "alice"))
+        #expect(isRead(context.privateChats[stablePeerID]?.last?.deliveryStatus, by: "alice"))
+        #expect(context.selectedPrivateChatPeer == stablePeerID)
+        #expect(context.deliveredMessageIDs == ["mine-short-1", "mine-short-2"])
+        #expect(context.notifyUIChangedCount == 2)
+    }
+
+    @Test @MainActor
+    func accountDMAck_doesNotTouchAnUnrelatedConversationWithTheSameMessageID() async {
+        let context = MockChatPrivateConversationContext()
+        let coordinator = ChatPrivateConversationCoordinator(context: context)
+        let stablePeerID = PeerID(hexData: Data(repeating: 0xC1, count: 32))
+        let unrelatedPeerID = PeerID(str: "1111222233334444")
+        context.privateChats[unrelatedPeerID] = [
+            makeIncomingMessage(id: "collision", sender: "me")
+        ]
+        context.queuedMessageIDsByPeerID[unrelatedPeerID] = ["collision"]
+
+        coordinator.handleDelivered(
+            NoisePayload(type: .delivered, data: Data("collision".utf8)),
+            senderPubkey: "feedface00112233",
+            convKey: stablePeerID
+        )
+
+        #expect(isDelivered(context.privateChats[unrelatedPeerID]?.first?.deliveryStatus, to: "me"))
+        #expect(context.deliveredMessageIDs.isEmpty)
+        #expect(context.queuedMessageIDsByPeerID[unrelatedPeerID] == ["collision"])
+        #expect(context.notifyUIChangedCount == 0)
     }
 
     @Test @MainActor
@@ -443,6 +522,180 @@ struct ChatPrivateConversationCoordinatorContextTests {
         #expect(isFailed(context.privateChats[peerID]?.first?.deliveryStatus))
     }
 
+    @Test @MainActor
+    func accountDM_handsOpenShortIDConversationToStableWhenOffline() async {
+        let context = MockChatPrivateConversationContext()
+        let coordinator = ChatPrivateConversationCoordinator(context: context)
+        let noiseKey = Data(repeating: 0xA7, count: 32)
+        let stablePeerID = PeerID(hexData: noiseKey)
+        let shortPeerID = stablePeerID.toShort()
+        let senderPubkey = "feedface00112233"
+        let now = Date()
+        context.displayNamesByPubkey[senderPubkey] = "bob"
+        context.selectedPrivateChatPeer = shortPeerID
+        context.privateChats[shortPeerID] = [
+            makeIncomingMessage(
+                id: "short-history",
+                sender: "me",
+                timestamp: now.addingTimeInterval(-30),
+                senderPeerID: context.myPeerID
+            ),
+            makeIncomingMessage(
+                id: "short-inbound",
+                sender: "bob",
+                timestamp: now.addingTimeInterval(-25),
+                senderPeerID: shortPeerID
+            )
+        ]
+        context.privateChats[stablePeerID] = [
+            makeIncomingMessage(
+                id: "stable-history",
+                sender: "bob",
+                timestamp: now.addingTimeInterval(-20),
+                senderPeerID: stablePeerID
+            )
+        ]
+        let payloadData = PrivateMessagePacket(messageID: "account-live-1", content: "live reply").encode()!
+
+        coordinator.handlePrivateMessage(
+            NoisePayload(type: .privateMessage, data: payloadData),
+            senderPubkey: senderPubkey,
+            convKey: stablePeerID,
+            id: MockChatPrivateConversationContext.dummyIdentity,
+            messageTimestamp: now
+        )
+
+        #expect(context.privateChats[shortPeerID] == nil)
+        #expect(context.privateChats[stablePeerID]?.map(\.id) == [
+            "short-history",
+            "short-inbound",
+            "stable-history",
+            "account-live-1"
+        ])
+        #expect(context.privateChats[stablePeerID]?[1].senderPeerID == stablePeerID)
+        #expect(context.privateChats[stablePeerID]?.last?.senderPeerID == stablePeerID)
+        #expect(context.migratedChats.contains(where: { $0.from == shortPeerID && $0.to == stablePeerID }))
+        #expect(context.selectedPrivateChatPeer == stablePeerID)
+        #expect(context.geoReadReceipts.map(\.messageID) == ["account-live-1"])
+        #expect(context.unreadPrivateMessages.isEmpty)
+        #expect(context.notifyUIChangedCount == 1)
+    }
+
+    @Test @MainActor
+    func accountDM_aliasMergePreservesTheCanonicalDestinationCopy() async {
+        let context = MockChatPrivateConversationContext()
+        let coordinator = ChatPrivateConversationCoordinator(context: context)
+        let noiseKey = Data(repeating: 0xA8, count: 32)
+        let stablePeerID = PeerID(hexData: noiseKey)
+        let shortPeerID = stablePeerID.toShort()
+        let senderPubkey = "feedface00112233"
+        let olderSource = makeIncomingMessage(
+            id: "duplicate-history",
+            sender: "bob",
+            content: "older source copy",
+            senderPeerID: shortPeerID
+        )
+        olderSource.deliveryStatus = .delivered(to: "me", at: Date(timeIntervalSince1970: 10))
+        let newerDestination = makeIncomingMessage(
+            id: "duplicate-history",
+            sender: "bob",
+            content: "newer destination copy",
+            senderPeerID: shortPeerID
+        )
+        newerDestination.deliveryStatus = .read(by: "me", at: Date(timeIntervalSince1970: 20))
+        context.privateChats[shortPeerID] = [olderSource]
+        context.privateChats[stablePeerID] = [newerDestination]
+        context.displayNamesByPubkey[senderPubkey] = "bob"
+        let payloadData = PrivateMessagePacket(messageID: "after-merge", content: "new reply").encode()!
+
+        coordinator.handlePrivateMessage(
+            NoisePayload(type: .privateMessage, data: payloadData),
+            senderPubkey: senderPubkey,
+            convKey: stablePeerID,
+            id: MockChatPrivateConversationContext.dummyIdentity,
+            messageTimestamp: Date()
+        )
+
+        let merged = context.privateChats[stablePeerID]?.first
+        #expect(context.privateChats[shortPeerID] == nil)
+        #expect(merged?.content == "newer destination copy")
+        #expect(isRead(merged?.deliveryStatus, by: "me"))
+        #expect(merged?.senderPeerID == stablePeerID)
+    }
+
+    @Test @MainActor
+    func accountDM_keepsTheConnectedShortIDConversationCanonical() async {
+        let context = MockChatPrivateConversationContext()
+        let coordinator = ChatPrivateConversationCoordinator(context: context)
+        let noiseKey = Data(repeating: 0xB8, count: 32)
+        let stablePeerID = PeerID(hexData: noiseKey)
+        let shortPeerID = stablePeerID.toShort()
+        let senderPubkey = "feedface00112233"
+        context.connectedPeers = [shortPeerID]
+        context.selectedPrivateChatPeer = stablePeerID
+        context.displayNamesByPubkey[senderPubkey] = "bob"
+        context.privateChats[stablePeerID] = [
+            makeIncomingMessage(id: "stable-history", senderPeerID: stablePeerID)
+        ]
+        let payloadData = PrivateMessagePacket(messageID: "connected-live-1", content: "still nearby").encode()!
+
+        coordinator.handlePrivateMessage(
+            NoisePayload(type: .privateMessage, data: payloadData),
+            senderPubkey: senderPubkey,
+            convKey: stablePeerID,
+            id: MockChatPrivateConversationContext.dummyIdentity,
+            messageTimestamp: Date()
+        )
+
+        #expect(context.privateChats[stablePeerID] == nil)
+        #expect(context.privateChats[shortPeerID]?.map(\.id) == ["stable-history", "connected-live-1"])
+        #expect(context.privateChats[shortPeerID]?.first?.senderPeerID == shortPeerID)
+        #expect(context.privateChats[shortPeerID]?.last?.senderPeerID == shortPeerID)
+        #expect(context.selectedPrivateChatPeer == shortPeerID)
+        #expect(context.geoReadReceipts.map(\.messageID) == ["connected-live-1"])
+    }
+
+    @Test @MainActor
+    func accountDM_duplicateDowngradeAckStillClearsTheRetainedOutbox() async {
+        let context = MockChatPrivateConversationContext()
+        let coordinator = ChatPrivateConversationCoordinator(context: context)
+        let stablePeerID = PeerID(hexData: Data(repeating: 0xE2, count: 32))
+        let message = makeIncomingMessage(id: "already-read", sender: "me")
+        message.deliveryStatus = .read(by: "bob", at: Date())
+        context.privateChats[stablePeerID] = [message]
+        context.queuedMessageIDsByPeerID[stablePeerID] = ["already-read"]
+
+        coordinator.handleDelivered(
+            NoisePayload(type: .delivered, data: Data("already-read".utf8)),
+            senderPubkey: "feedface00112233",
+            convKey: stablePeerID
+        )
+
+        #expect(isRead(context.privateChats[stablePeerID]?.first?.deliveryStatus, by: "bob"))
+        #expect(context.deliveredMessageIDs == ["already-read"])
+        #expect(context.notifyUIChangedCount == 0)
+    }
+
+    @Test @MainActor
+    func accountDMAck_clearsRetainedMessageAfterConversationWasRemoved() async {
+        let context = MockChatPrivateConversationContext()
+        let coordinator = ChatPrivateConversationCoordinator(context: context)
+        let stablePeerID = PeerID(hexData: Data(repeating: 0xE3, count: 32))
+        let shortPeerID = stablePeerID.toShort()
+        context.queuedMessageIDsByPeerID[shortPeerID] = ["cleared-bubble"]
+
+        coordinator.handleDelivered(
+            NoisePayload(type: .delivered, data: Data("cleared-bubble".utf8)),
+            senderPubkey: "feedface00112233",
+            convKey: stablePeerID
+        )
+
+        #expect(context.privateChats.isEmpty)
+        #expect(context.queuedMessageIDsByPeerID[shortPeerID] == nil)
+        #expect(context.deliveredMessageIDs == ["cleared-bubble"])
+        #expect(context.notifyUIChangedCount == 0)
+    }
+
     @Test @MainActor
     func handleViewingThisChat_clearsUnreadAndSendsRoutedReadReceiptOnce() async {
         let context = MockChatPrivateConversationContext()

bitchatTests/ChatTransportEventCoordinatorContextTests.swift

@@ -133,11 +133,17 @@ private final class MockChatTransportEventContext: ChatTransportEventContext {
     // Delivery status
     var applyMessageDeliveryStatusResult = true
     var deliveryStatusesByMessageID: [String: DeliveryStatus] = [:]
-    private(set) var appliedDeliveryStatuses: [(messageID: String, status: DeliveryStatus)] = []
+    private(set) var appliedDeliveryStatuses: [
+        (messageID: String, status: DeliveryStatus, peerIDAliases: Set<PeerID>)
+    ] = []
 
     @discardableResult
-    func applyMessageDeliveryStatus(_ messageID: String, status: DeliveryStatus) -> Bool {
+    func applyAcknowledgedMessageDeliveryStatus(
-        appliedDeliveryStatuses.append((messageID, status))
+        _ messageID: String,
+        status: DeliveryStatus,
+        from peerIDAliases: Set<PeerID>
+    ) -> Bool {
+        appliedDeliveryStatuses.append((messageID, status, peerIDAliases))
         return applyMessageDeliveryStatusResult
     }
 
@@ -417,6 +423,10 @@ struct ChatTransportEventCoordinatorContextTests {
         let peerID = PeerID(str: "99aabbccddeeff00")
         let noiseKey = Data(repeating: 0x44, count: 32)
         context.peersByID[peerID] = BitchatPeer(peerID: peerID, noisePublicKey: noiseKey, nickname: "alice")
+        let stablePeerID = PeerID(hexData: noiseKey)
+        let staleStablePeerID = PeerID(hexData: Data(repeating: 0x55, count: 32))
+        context.cacheStablePeerID(staleStablePeerID, for: peerID)
+        context.noiseSessionKeysByPeerID[peerID] = noiseKey
 
         // Inbound private message: decoded, handled, and delivery-acked.
         let packet = PrivateMessagePacket(messageID: "pm-1", content: "hi there")
@@ -438,6 +448,8 @@ struct ChatTransportEventCoordinatorContextTests {
         await drainMainActorTasks()
         #expect(context.appliedDeliveryStatuses.count == 2)
         #expect(context.appliedDeliveryStatuses[0].messageID == "m-1")
+        #expect(context.appliedDeliveryStatuses[0].peerIDAliases == [peerID, stablePeerID])
+        #expect(!context.appliedDeliveryStatuses[0].peerIDAliases.contains(staleStablePeerID))
         if case .delivered(let to, _) = context.appliedDeliveryStatuses[0].status {
             #expect(to == "alice")
         } else {

bitchatTests/ChatVerificationCoordinatorContextTests.swift

@@ -98,6 +98,7 @@ private final class MockChatVerificationContext: ChatVerificationContext {
     private(set) var installedCallbacks: (onPeerAuthenticated: (PeerID, String) -> Void, onHandshakeRequired: (PeerID) -> Void)?
     private(set) var triggeredHandshakes: [PeerID] = []
     private(set) var privateMediaAuthenticatedPeers: [PeerID] = []
+    private(set) var securePrivateMessageRetryAliases: [[PeerID]] = []
     private(set) var sentChallenges: [(peerID: PeerID, noiseKeyHex: String, nonceA: Data)] = []
     private(set) var sentResponses: [(peerID: PeerID, noiseKeyHex: String, nonceA: Data)] = []
 
@@ -118,6 +119,10 @@ private final class MockChatVerificationContext: ChatVerificationContext {
         privateMediaAuthenticatedPeers.append(peerID)
     }
 
+    func retrySecurePrivateMessagesAfterAuthentication(for peerIDAliases: [PeerID]) {
+        securePrivateMessageRetryAliases.append(peerIDAliases)
+    }
+
     func sendVerifyChallenge(to peerID: PeerID, noiseKeyHex: String, nonceA: Data) {
         sentChallenges.append((peerID, noiseKeyHex, nonceA))
     }
@@ -269,6 +274,10 @@ struct ChatVerificationCoordinatorContextTests {
         let peerID = PeerID(str: "1122334455667788")
         let noiseKey = Data(repeating: 0x33, count: 32)
         context.noiseSessionKeysByPeerID[peerID] = noiseKey
+        context.cacheStablePeerID(
+            PeerID(hexData: Data(repeating: 0x44, count: 32)),
+            for: peerID
+        )
         context.verifiedFingerprints = ["fp-verified"]
 
         coordinator.setupNoiseCallbacks()
@@ -279,9 +288,11 @@ struct ChatVerificationCoordinatorContextTests {
         callbacks?.onPeerAuthenticated(peerID, "fp-verified")
         await waitForMainQueue()
         #expect(context.encryptionStatuses[peerID] == .noiseVerified)
-        #expect(context.stablePeerIDCache[peerID] == PeerID(hexData: noiseKey))
+        let stablePeerID = PeerID(hexData: noiseKey)
+        #expect(context.stablePeerIDCache[peerID] == stablePeerID)
         #expect(context.invalidatedEncryptionCachePeers.contains(peerID))
         #expect(context.privateMediaAuthenticatedPeers == [peerID])
+        #expect(context.securePrivateMessageRetryAliases == [[peerID, stablePeerID]])
 
         // Handshake required -> handshaking status.
         callbacks?.onHandshakeRequired(peerID)

bitchatTests/ChatViewModelDeliveryStatusTests.swift

@@ -298,6 +298,137 @@ struct ChatViewModelDeliveryStatusTests {
         }())
     }
 
+    @Test @MainActor
+    func authenticatedNoiseAckCannotClearAnotherPeersRetryState() async {
+        let (viewModel, transport) = makeTestableViewModel()
+        let intendedPeer = PeerID(str: "0102030405060708")
+        let otherPeer = PeerID(str: "1112131415161718")
+        let messageID = "noise-peer-bound-ack"
+
+        viewModel.seedPrivateChat(
+            [
+                BitchatMessage(
+                    id: messageID,
+                    sender: viewModel.nickname,
+                    content: "Keep retrying",
+                    timestamp: Date(),
+                    isRelay: false,
+                    isPrivate: true,
+                    recipientNickname: "Intended",
+                    senderPeerID: viewModel.myPeerID,
+                    deliveryStatus: .sent
+                )
+            ],
+            for: intendedPeer
+        )
+        transport.reachablePeers.insert(intendedPeer)
+        viewModel.messageRouter.sendPrivate(
+            "Keep retrying",
+            to: intendedPeer,
+            recipientNickname: "Intended",
+            messageID: messageID
+        )
+        #expect(transport.sentPrivateMessages.count == 1)
+
+        // This models a decrypted Noise receipt: the transport-authenticated
+        // peer is authoritative, not the attacker-controlled message ID.
+        viewModel.didReceiveNoisePayload(
+            from: otherPeer,
+            type: .delivered,
+            payload: Data(messageID.utf8),
+            timestamp: Date()
+        )
+        for _ in 0..<10 { await Task.yield() }
+
+        #expect(isSent(viewModel.conversations.deliveryStatus(forMessageID: messageID)))
+        viewModel.messageRouter.flushOutbox(for: intendedPeer)
+        #expect(transport.sentPrivateMessages.count == 2)
+
+        viewModel.didReceiveNoisePayload(
+            from: intendedPeer,
+            type: .delivered,
+            payload: Data(messageID.utf8),
+            timestamp: Date()
+        )
+        for _ in 0..<10 { await Task.yield() }
+
+        #expect(isDelivered(viewModel.conversations.deliveryStatus(forMessageID: messageID)))
+        viewModel.messageRouter.flushOutbox(for: intendedPeer)
+        #expect(transport.sentPrivateMessages.count == 2)
+    }
+
+    @Test @MainActor
+    func authenticatedNoiseAckClearsOnlyIntendedPeersPrivateMediaRetry() async throws {
+        let (viewModel, transport) = makeTestableViewModel()
+        let intendedPeer = PeerID(str: "0102030405060708")
+        let otherPeer = PeerID(str: "1112131415161718")
+        let fileName = "voice_0011223344556677.m4a"
+        let content = Data("voice".utf8)
+
+        transport.privateMediaPolicies[intendedPeer] = .encrypted
+        transport.privateMediaReceiptSessionGenerations[intendedPeer] = UUID()
+        viewModel.selectedPrivateChatPeer = intendedPeer
+        let coordinator = ChatMediaTransferCoordinator(
+            context: viewModel,
+            prepareVoiceNotePacket: { _ in
+                BitchatFilePacket(
+                    fileName: fileName,
+                    fileSize: UInt64(content.count),
+                    mimeType: "audio/mp4",
+                    content: content
+                )
+            },
+            transferIDFactory: { "\($0)-receipt-ack" }
+        )
+        viewModel.mediaTransferCoordinator = coordinator
+
+        let directory = FileManager.default.temporaryDirectory
+            .appendingPathComponent(
+                "scoped-media-ack-\(UUID().uuidString)",
+                isDirectory: true
+            )
+        try FileManager.default.createDirectory(
+            at: directory,
+            withIntermediateDirectories: true
+        )
+        let sourceURL = directory.appendingPathComponent(fileName)
+        try content.write(to: sourceURL)
+        defer { try? FileManager.default.removeItem(at: directory) }
+
+        coordinator.sendVoiceNote(at: sourceURL)
+        #expect(await TestHelpers.waitUntil(
+            {
+                transport.sentPrivateFiles.count == 1
+                    && coordinator.retainedReconnectRetryCount == 1
+            },
+            timeout: TestConstants.longTimeout
+        ))
+        let messageID = try #require(
+            viewModel.privateChats[intendedPeer]?.first?.id
+        )
+        let transferID = try #require(
+            transport.sentPrivateFiles.first?.transferID
+        )
+
+        #expect(!viewModel.deliveryCoordinator
+            .updateAcknowledgedMessageDeliveryStatus(
+                messageID,
+                status: .delivered(to: "Other", at: Date()),
+                from: [otherPeer]
+            ))
+        #expect(coordinator.retainedReconnectRetryCount == 1)
+        #expect(transport.cancelledTransfers.isEmpty)
+
+        #expect(viewModel.deliveryCoordinator
+            .updateAcknowledgedMessageDeliveryStatus(
+                messageID,
+                status: .delivered(to: "Intended", at: Date()),
+                from: [intendedPeer]
+            ))
+        #expect(coordinator.retainedReconnectRetryCount == 0)
+        #expect(transport.cancelledTransfers == [transferID])
+    }
+
     @Test @MainActor
     func cleanupOldReadReceipts_removesReceiptIDsWithoutMessages() async {
         let (viewModel, transport) = makeTestableViewModel()
@@ -577,12 +708,26 @@ private final class MockChatDeliveryContext: ChatDeliveryContext {
     var isStartupPhase = false
     private(set) var notifyUIChangedCount = 0
     private(set) var markedDeliveredMessageIDs: [String] = []
+    private(set) var peerBoundDeliveredMessages: [(messageID: String, peerIDs: Set<PeerID>)] = []
 
     @discardableResult
     func setDeliveryStatus(_ status: DeliveryStatus, forMessageID messageID: String) -> Bool {
         store.setDeliveryStatus(status, forMessageID: messageID)
     }
 
+    @discardableResult
+    func setDeliveryStatus(
+        _ status: DeliveryStatus,
+        forMessageID messageID: String,
+        inDirectPeerAliases peerIDs: Set<PeerID>
+    ) -> Bool {
+        store.setDeliveryStatus(
+            status,
+            forMessageID: messageID,
+            inDirectPeerAliases: peerIDs
+        )
+    }
+
     func deliveryStatus(forMessageID messageID: String) -> DeliveryStatus? {
         store.deliveryStatus(forMessageID: messageID)
     }
@@ -604,6 +749,24 @@ private final class MockChatDeliveryContext: ChatDeliveryContext {
     func markMessageDelivered(_ messageID: String) {
         markedDeliveredMessageIDs.append(messageID)
     }
+
+    func markMessageDelivered(_ messageID: String, from peerIDs: Set<PeerID>) {
+        peerBoundDeliveredMessages.append((messageID, peerIDs))
+    }
+
+    func isOutgoingPrivateMessage(_ messageID: String, toAny peerIDs: Set<PeerID>) -> Bool {
+        peerIDs.contains { peerID in
+            contextMessages(for: peerID).contains { message in
+                message.id == messageID && message.senderPeerID == localPeerID
+            }
+        }
+    }
+
+    private let localPeerID = PeerID(str: "aabbccddeeff0011")
+
+    private func contextMessages(for peerID: PeerID) -> [BitchatMessage] {
+        store.conversationsByID[.directPeer(peerID)]?.messages ?? []
+    }
 }
 
 @MainActor
@@ -685,7 +848,151 @@ struct ChatDeliveryCoordinatorContextTests {
 
         #expect(isRead(coordinator.deliveryStatus(for: messageID)))
         #expect(context.notifyUIChangedCount == 1)
-        #expect(context.markedDeliveredMessageIDs == [messageID])
+        #expect(context.markedDeliveredMessageIDs.isEmpty)
+        #expect(context.peerBoundDeliveredMessages.count == 1)
+        #expect(context.peerBoundDeliveredMessages[0].messageID == messageID)
+        #expect(context.peerBoundDeliveredMessages[0].peerIDs == [peerID])
+    }
+
+    @Test @MainActor
+    func authenticatedReceiptWithCollidingIDUpdatesOnlyAuthenticatedAliases() async {
+        let context = MockChatDeliveryContext()
+        let coordinator = ChatDeliveryCoordinator(context: context)
+        let ephemeralPeerID = PeerID(str: "0102030405060708")
+        let stablePeerID = PeerID(hexData: Data(repeating: 0x08, count: 32))
+        let otherPeerID = PeerID(str: "1112131415161718")
+        let messageID = "authenticated-receipt-collision"
+        let mirroredMessage = makePrivateMessage(id: messageID, status: .sent)
+
+        context.store.append(mirroredMessage, to: .directPeer(ephemeralPeerID))
+        context.store.append(mirroredMessage, to: .directPeer(stablePeerID))
+        context.store.append(
+            makePrivateMessage(id: messageID, status: .sent),
+            to: .directPeer(otherPeerID)
+        )
+        context.store.append(makePublicMessage(id: messageID, status: .sent), to: .mesh)
+
+        let aliases: Set<PeerID> = [ephemeralPeerID, stablePeerID]
+        let didUpdate = coordinator.updateAcknowledgedMessageDeliveryStatus(
+            messageID,
+            status: .delivered(to: "Peer", at: Date()),
+            from: aliases
+        )
+
+        #expect(didUpdate)
+        #expect(isDelivered(
+            context.store.conversation(for: .directPeer(ephemeralPeerID))
+                .message(withID: messageID)?.deliveryStatus
+        ))
+        #expect(isDelivered(
+            context.store.conversation(for: .directPeer(stablePeerID))
+                .message(withID: messageID)?.deliveryStatus
+        ))
+        #expect(isSent(
+            context.store.conversation(for: .directPeer(otherPeerID))
+                .message(withID: messageID)?.deliveryStatus
+        ))
+        #expect(isSent(
+            context.store.conversation(for: .mesh)
+                .message(withID: messageID)?.deliveryStatus
+        ))
+        #expect(context.peerBoundDeliveredMessages.count == 1)
+        #expect(context.peerBoundDeliveredMessages[0].messageID == messageID)
+        #expect(context.peerBoundDeliveredMessages[0].peerIDs == aliases)
+        #expect(context.notifyUIChangedCount == 1)
+    }
+
+    @Test @MainActor
+    func authenticatedReceiptRemainsScopedAfterPeerAliasMigration() async {
+        let context = MockChatDeliveryContext()
+        let coordinator = ChatDeliveryCoordinator(context: context)
+        let ephemeralPeerID = PeerID(str: "2122232425262728")
+        let stablePeerID = PeerID(hexData: Data(repeating: 0x28, count: 32))
+        let otherPeerID = PeerID(str: "3132333435363738")
+        let messageID = "authenticated-receipt-after-migration"
+
+        context.store.append(
+            makePrivateMessage(id: messageID, status: .sent),
+            to: .directPeer(ephemeralPeerID)
+        )
+        context.store.append(
+            makePrivateMessage(id: messageID, status: .sent),
+            to: .directPeer(otherPeerID)
+        )
+        context.store.migrateConversation(
+            from: .directPeer(ephemeralPeerID),
+            to: .directPeer(stablePeerID)
+        )
+
+        let didUpdate = coordinator.updateAcknowledgedMessageDeliveryStatus(
+            messageID,
+            status: .read(by: "Peer", at: Date()),
+            from: [ephemeralPeerID, stablePeerID]
+        )
+
+        #expect(didUpdate)
+        #expect(context.store.conversationsByID[.directPeer(ephemeralPeerID)] == nil)
+        #expect(isRead(
+            context.store.conversation(for: .directPeer(stablePeerID))
+                .message(withID: messageID)?.deliveryStatus
+        ))
+        #expect(isSent(
+            context.store.conversation(for: .directPeer(otherPeerID))
+                .message(withID: messageID)?.deliveryStatus
+        ))
+    }
+
+    @Test @MainActor
+    func receiptFromWrongPeerDoesNotUpdateOrTerminalizeOutgoingMessage() async {
+        let context = MockChatDeliveryContext()
+        let coordinator = ChatDeliveryCoordinator(context: context)
+        let intendedPeer = PeerID(str: "0102030405060708")
+        let otherPeer = PeerID(str: "1112131415161718")
+        let messageID = "wrong-peer-receipt"
+        context.store.append(
+            makePrivateMessage(id: messageID, status: .sent),
+            to: .directPeer(intendedPeer)
+        )
+
+        coordinator.didReceiveReadReceipt(
+            ReadReceipt(
+                originalMessageID: messageID,
+                readerID: otherPeer,
+                readerNickname: "Other"
+            )
+        )
+
+        #expect(isSent(coordinator.deliveryStatus(for: messageID)))
+        #expect(context.peerBoundDeliveredMessages.isEmpty)
+        #expect(context.markedDeliveredMessageIDs.isEmpty)
+        #expect(context.notifyUIChangedCount == 0)
+    }
+
+    @Test @MainActor
+    func rejectedStaleReceiptDoesNotTerminalizeRetryState() async {
+        let context = MockChatDeliveryContext()
+        let coordinator = ChatDeliveryCoordinator(context: context)
+        let peerID = PeerID(str: "0102030405060708")
+        let messageID = "stale-receipt"
+        context.store.append(
+            makePrivateMessage(
+                id: messageID,
+                status: .read(by: "Peer", at: Date())
+            ),
+            to: .directPeer(peerID)
+        )
+
+        let didUpdate = coordinator.updateAcknowledgedMessageDeliveryStatus(
+            messageID,
+            status: .delivered(to: "Peer", at: Date()),
+            from: [peerID]
+        )
+
+        #expect(!didUpdate)
+        #expect(isRead(coordinator.deliveryStatus(for: messageID)))
+        #expect(context.peerBoundDeliveredMessages.isEmpty)
+        #expect(context.markedDeliveredMessageIDs.isEmpty)
+        #expect(context.notifyUIChangedCount == 0)
     }
 
     @Test @MainActor

bitchatTests/ConversationStoreTests.swift

@@ -755,6 +755,71 @@ struct ConversationStoreTests {
         #expect(statusChangedIDs.isEmpty)
     }
 
+    @Test("peer-scoped receipt updates only authenticated direct aliases")
+    @MainActor
+    func peerScopedReceiptUpdatesOnlyAuthenticatedDirectAliases() {
+        let store = ConversationStore()
+        let ephemeralPeer = PeerID(str: "0102030405060708")
+        let stablePeer = PeerID(hexData: Data(repeating: 0x08, count: 32))
+        let otherPeer = PeerID(str: "1112131415161718")
+        let ephemeral = ConversationID.directPeer(ephemeralPeer)
+        let stable = ConversationID.directPeer(stablePeer)
+        let other = ConversationID.directPeer(otherPeer)
+        let messageID = "scoped-receipt"
+        let mirrored = makeMessage(
+            id: messageID,
+            timestamp: 1,
+            isPrivate: true,
+            deliveryStatus: .sent
+        )
+        store.upsertByID(mirrored, in: ephemeral)
+        store.upsertByID(mirrored, in: stable)
+        store.upsertByID(
+            makeMessage(
+                id: messageID,
+                timestamp: 1,
+                isPrivate: true,
+                deliveryStatus: .sent
+            ),
+            in: other
+        )
+        store.upsertByID(
+            makeMessage(id: messageID, timestamp: 1, deliveryStatus: .sent),
+            in: .mesh
+        )
+
+        var cancellables = Set<AnyCancellable>()
+        var publishedIDs: [ConversationID] = []
+        for id in [ephemeral, stable, other, .mesh] {
+            store.conversation(for: id).objectWillChange
+                .sink { publishedIDs.append(id) }
+                .store(in: &cancellables)
+        }
+        var statusChangedIDs: [ConversationID] = []
+        store.changes
+            .sink { change in
+                if case .statusChanged(let id, messageID, _) = change,
+                   messageID == "scoped-receipt" {
+                    statusChangedIDs.append(id)
+                }
+            }
+            .store(in: &cancellables)
+
+        let delivered = DeliveryStatus.delivered(to: "bob", at: Date())
+        #expect(store.setDeliveryStatus(
+            delivered,
+            forMessageID: messageID,
+            inDirectPeerAliases: [ephemeralPeer, stablePeer]
+        ))
+
+        #expect(Set(publishedIDs) == Set([ephemeral, stable]))
+        #expect(Set(statusChangedIDs) == Set([ephemeral, stable]))
+        #expect(store.conversation(for: ephemeral).message(withID: messageID)?.deliveryStatus == delivered)
+        #expect(store.conversation(for: stable).message(withID: messageID)?.deliveryStatus == delivered)
+        #expect(store.conversation(for: other).message(withID: messageID)?.deliveryStatus == .sent)
+        #expect(store.conversation(for: .mesh).message(withID: messageID)?.deliveryStatus == .sent)
+    }
+
     // MARK: - Invariant audit (field observability)
 
     /// A store exercised through every intent family: public + geohash +

bitchatTests/Mocks/MockTransport.swift

@@ -65,11 +65,15 @@ final class MockTransport: Transport, PrivateMediaDeletionPersisting {
     var peerFingerprints: [PeerID: String] = [:]
     var peerNoiseStates: [PeerID: LazyHandshakeState] = [:]
     var privateMediaPolicies: [PeerID: PrivateMediaSendPolicy] = [:]
+    var privateMediaReceiptSessionGenerations: [PeerID: UUID] = [:]
     var persistDeletedPrivateMediaResult = true
     var deferDeletedPrivateMediaPersistence = false
     private var pendingDeletedPrivateMediaCompletions: [
         @MainActor (Bool) -> Void
     ] = []
+    /// Optional synchronous hook for send-ordering tests (for example, an ack
+    /// arriving before the router's send call returns).
+    var onSendPrivateMessage: (@MainActor (_ messageID: String) -> Void)?
     private let mockKeychain = MockKeychain()
 
     // MARK: - Transport Protocol Implementation
@@ -174,6 +178,11 @@ final class MockTransport: Transport, PrivateMediaDeletionPersisting {
 
     func sendPrivateMessage(_ content: String, to peerID: PeerID, recipientNickname: String, messageID: String) {
         sentPrivateMessages.append((content, peerID, recipientNickname, messageID))
+        if let onSendPrivateMessage {
+            MainActor.assumeIsolated {
+                onSendPrivateMessage(messageID)
+            }
+        }
     }
 
     func sendReadReceipt(_ receipt: ReadReceipt, to peerID: PeerID) {
@@ -215,6 +224,12 @@ final class MockTransport: Transport, PrivateMediaDeletionPersisting {
         privateMediaPolicies[peerID] ?? .encrypted
     }
 
+    func authenticatedPrivateMediaReceiptSessionGeneration(
+        to peerID: PeerID
+    ) -> UUID? {
+        privateMediaReceiptSessionGenerations[peerID]
+    }
+
     func resolvePrivateMediaSendPolicy(
         to peerID: PeerID,
         completion: @escaping @MainActor (PrivateMediaSendPolicy) -> Void

bitchatTests/Performance/PerformanceBaselineTests.swift

@@ -690,12 +690,29 @@ private final class PerfDeliveryContext: ChatDeliveryContext {
 
     func notifyUIChanged() {}
     func markMessageDelivered(_ messageID: String) {}
+    func markMessageDelivered(_ messageID: String, from peerIDs: Set<PeerID>) {}
+    func isOutgoingPrivateMessage(_ messageID: String, toAny peerIDs: Set<PeerID>) -> Bool {
+        true
+    }
 
     @discardableResult
     func setDeliveryStatus(_ status: DeliveryStatus, forMessageID messageID: String) -> Bool {
         store.setDeliveryStatus(status, forMessageID: messageID)
     }
 
+    @discardableResult
+    func setDeliveryStatus(
+        _ status: DeliveryStatus,
+        forMessageID messageID: String,
+        inDirectPeerAliases peerIDs: Set<PeerID>
+    ) -> Bool {
+        store.setDeliveryStatus(
+            status,
+            forMessageID: messageID,
+            inDirectPeerAliases: peerIDs
+        )
+    }
+
     func deliveryStatus(forMessageID messageID: String) -> DeliveryStatus? {
         store.deliveryStatus(forMessageID: messageID)
     }

bitchatTests/Services/BridgeCourierServiceTests.swift

@@ -203,6 +203,134 @@ struct BridgeCourierServiceTests {
         #expect(confirmed.sealRequests.isEmpty)
     }
 
+    @Test func sameMessageIDIsScopedByRecipientAcrossRejectedActiveAndPersistedState() {
+        let fileURL = FileManager.default.temporaryDirectory
+            .appendingPathComponent("bridge-dedup-\(UUID().uuidString).json")
+        defer { try? FileManager.default.removeItem(at: fileURL) }
+        let rejectedKey = Fixture.randomKey()
+        let firstKey = Fixture.randomKey()
+        let secondKey = Fixture.randomKey()
+        let thirdKey = Fixture.randomKey()
+        let messageID = "recipient-scoped-collision"
+
+        let fixture = Fixture(dedupStore: BridgeDropDedupStore(fileURL: fileURL))
+        fixture.sealResult = makeEnvelope(
+            recipientKey: rejectedKey,
+            ciphertext: Data(
+                repeating: 7,
+                count: BridgeCourierService.Limits.maxDropEnvelopeBytes + 1
+            )
+        )
+        var rejectedResults: [Bool] = []
+        fixture.service.depositDrop(
+            content: "rejected",
+            messageID: messageID,
+            recipientNoiseKey: rejectedKey
+        ) { rejectedResults.append($0) }
+        #expect(rejectedResults == [false])
+
+        fixture.sealResult = makeEnvelope(recipientKey: firstKey)
+        fixture.automaticPublishResult = nil
+        var firstResults: [Bool] = []
+        var secondResults: [Bool] = []
+        var duplicateFirstResults: [Bool] = []
+        fixture.service.depositDrop(
+            content: "first",
+            messageID: messageID,
+            recipientNoiseKey: firstKey
+        ) { firstResults.append($0) }
+        fixture.service.depositDrop(
+            content: "second",
+            messageID: messageID,
+            recipientNoiseKey: secondKey
+        ) { secondResults.append($0) }
+        fixture.service.depositDrop(
+            content: "first duplicate",
+            messageID: messageID,
+            recipientNoiseKey: firstKey
+        ) { duplicateFirstResults.append($0) }
+
+        #expect(fixture.publishedEvents.count == 2)
+        #expect(fixture.pendingPublishCompletions.count == 2)
+        #expect(duplicateFirstResults == [false])
+        #expect(firstResults.isEmpty)
+        #expect(secondResults.isEmpty)
+
+        fixture.resolveNextPublish(true)
+        fixture.resolveNextPublish(true)
+        #expect(firstResults == [true])
+        #expect(secondResults == [true])
+        fixture.service.flushDedupSnapshot()
+
+        let relaunched = Fixture(
+            dedupStore: BridgeDropDedupStore(fileURL: fileURL)
+        )
+        relaunched.sealResult = makeEnvelope(recipientKey: thirdKey)
+        var relaunchResults: [Bool] = []
+        relaunched.service.depositDrop(
+            content: "first",
+            messageID: messageID,
+            recipientNoiseKey: firstKey
+        ) { relaunchResults.append($0) }
+        relaunched.service.depositDrop(
+            content: "second",
+            messageID: messageID,
+            recipientNoiseKey: secondKey
+        ) { relaunchResults.append($0) }
+        relaunched.service.depositDrop(
+            content: "third",
+            messageID: messageID,
+            recipientNoiseKey: thirdKey
+        ) { relaunchResults.append($0) }
+
+        #expect(relaunchResults == [false, false, true])
+        #expect(relaunched.sealRequests.count == 1)
+        #expect(relaunched.sealRequests.first?.key == thirdKey)
+        #expect(relaunched.publishedEvents.count == 1)
+    }
+
+    @Test func legacyPublishedMessageIDIsWildcardUntilItsOriginalExpiry() {
+        let fileURL = FileManager.default.temporaryDirectory
+            .appendingPathComponent("bridge-dedup-\(UUID().uuidString).json")
+        defer { try? FileManager.default.removeItem(at: fileURL) }
+        var date = Date()
+        let messageID = "legacy-wildcard"
+        let recipientKey = Fixture.randomKey()
+        let store = BridgeDropDedupStore(fileURL: fileURL)
+        store.save(BridgeDropDedupStore.Snapshot(
+            publishedDropKeys: [messageID: date],
+            seenDropEventIDs: [:]
+        ))
+
+        let fixture = Fixture(
+            now: { date },
+            dedupStore: BridgeDropDedupStore(fileURL: fileURL)
+        )
+        fixture.sealResult = makeEnvelope(recipientKey: recipientKey)
+        var results: [Bool] = []
+        fixture.service.depositDrop(
+            content: "legacy",
+            messageID: messageID,
+            recipientNoiseKey: recipientKey
+        ) { results.append($0) }
+        #expect(results == [false])
+        #expect(fixture.sealRequests.isEmpty)
+
+        date = date.addingTimeInterval(CourierEnvelope.maxLifetimeSeconds + 1)
+        fixture.service.depositDrop(
+            content: "after expiry",
+            messageID: messageID,
+            recipientNoiseKey: recipientKey
+        ) { results.append($0) }
+        #expect(results == [false, true])
+        #expect(fixture.publishedEvents.count == 1)
+        fixture.service.flushDedupSnapshot()
+
+        let snapshot = BridgeDropDedupStore(fileURL: fileURL).load()
+        #expect(snapshot.publishedDropKeys[messageID] == nil)
+        #expect(snapshot.publishedDropKeys.count == 1)
+    }
+
     @Test func panicWipeInvalidatesInFlightPublishCompletion() throws {
         let fileURL = FileManager.default.temporaryDirectory
             .appendingPathComponent("bridge-dedup-\(UUID().uuidString).json")
@@ -297,8 +425,10 @@ struct BridgeCourierServiceTests {
         #expect(firstResults == [false])
 
         // The evicted first drop is deposit-able again (slot released).
+        let sealCountBeforeRetry = fixture.sealRequests.count
         fixture.service.depositDrop(content: "0-retry", messageID: firstID, recipientNoiseKey: key)
-        #expect(fixture.service.pendingDrops.last?.dedupKey == firstID)
+        #expect(fixture.sealRequests.count == sealCountBeforeRetry + 1)
+        #expect(fixture.service.pendingDrops.count == BridgeCourierService.Limits.maxPendingDrops)
     }
 
     @Test func oversizeDropConsumesSlotInsteadOfChurning() {

bitchatTests/Services/MessageOutboxStoreTests.swift

@@ -207,6 +207,42 @@ struct MessageOutboxStoreTests {
         #expect(MessageOutboxStore(keychain: keychain, fileURL: fileURL).load().isEmpty)
     }
 
+    @Test func deferredScopedRemovalTombstoneFiltersOnlySelectedPeer() {
+        let fileURL = makeTempURL()
+        defer { try? FileManager.default.removeItem(at: fileURL) }
+        let keychain = MockKeychain()
+        let acknowledgedPeer = PeerID(str: "0000000000000001")
+        let otherPeer = PeerID(str: "0000000000000002")
+        MessageOutboxStore(keychain: keychain, fileURL: fileURL).save([
+            acknowledgedPeer: [makeMessage("shared-id", content: "for acknowledged peer")],
+            otherPeer: [makeMessage("shared-id", content: "for other peer")]
+        ])
+
+        var protectedDataUnavailable = true
+        let restored = MessageOutboxStore(
+            keychain: keychain,
+            fileURL: fileURL,
+            readData: { url in
+                if protectedDataUnavailable {
+                    throw NSError(domain: NSCocoaErrorDomain, code: NSFileReadNoPermissionError)
+                }
+                return try Data(contentsOf: url)
+            }
+        )
+        #expect(restored.load().isEmpty)
+        restored.recordRemoval(messageID: "shared-id", for: [acknowledgedPeer])
+        restored.save([:])
+
+        protectedDataUnavailable = false
+        let recovered = restored.retryDeferredLoad()
+        #expect(recovered?[acknowledgedPeer] == nil)
+        #expect(recovered?[otherPeer]?.map(\.messageID) == ["shared-id"])
+
+        let relaunched = MessageOutboxStore(keychain: keychain, fileURL: fileURL).load()
+        #expect(relaunched[acknowledgedPeer] == nil)
+        #expect(relaunched[otherPeer]?.map(\.messageID) == ["shared-id"])
+    }
+
     @Test func wipeRemovesFileAndKey() {
         let fileURL = makeTempURL()
         let keychain = MockKeychain()

bitchatTests/Services/MessageRouterTests.swift

@@ -79,18 +79,231 @@ struct MessageRouterTests {
     }
 
     @Test @MainActor
-    func sendPrivate_connectedSendIsNotRetained() async {
+    func peerBoundDeliveryAckCannotClearAnotherPeersRetainedMessage() async {
+        let intendedPeer = PeerID(str: "0000000000000023")
+        let otherPeer = PeerID(str: "0000000000000024")
+        let transport = MockTransport()
+        transport.reachablePeers = [intendedPeer, otherPeer]
+
+        let router = MessageRouter(transports: [transport])
+        router.sendPrivate(
+            "Secret",
+            to: intendedPeer,
+            recipientNickname: "Intended",
+            messageID: "peer-bound-ack"
+        )
+        #expect(transport.sentPrivateMessages.count == 1)
+
+        // Even a receipt arriving over another authenticated conversation
+        // must not terminalize the intended peer's retained retry.
+        router.markDelivered("peer-bound-ack", from: [otherPeer])
+        router.flushOutbox(for: intendedPeer)
+        #expect(transport.sentPrivateMessages.count == 2)
+
+        router.markDelivered("peer-bound-ack", from: [intendedPeer])
+        router.flushOutbox(for: intendedPeer)
+        #expect(transport.sentPrivateMessages.count == 2)
+    }
+
+    @Test @MainActor
+    func sendPrivate_connectedSecureSendRetainsUntilDeliveryAck() async {
         let peerID = PeerID(str: "0000000000000007")
         let transport = MockTransport()
         transport.connectedPeers.insert(peerID)
         transport.reachablePeers.insert(peerID)
+        transport.securePeers = [peerID]
 
         let router = MessageRouter(transports: [transport])
         router.sendPrivate("Hello", to: peerID, recipientNickname: "Peer", messageID: "m7")
         #expect(transport.sentPrivateMessages.count == 1)
 
-        router.flushOutbox(for: peerID)
+        // A newly authenticated/replacement session retries the retained
+        // message instead of losing the first ciphertext to a stale session.
+        router.retrySecurePrivateMessagesAfterAuthentication(for: [peerID])
+        #expect(transport.sentPrivateMessages.count == 2)
+
+        router.markDelivered("m7")
+        router.retrySecurePrivateMessagesAfterAuthentication(for: [peerID])
+        #expect(transport.sentPrivateMessages.count == 2)
+    }
+
+    @Test @MainActor
+    func authenticationRetry_matchesStableOutboxAliasWithoutDoubleSending() async {
+        let shortPeerID = PeerID(str: "0000000000000019")
+        let stablePeerID = PeerID(hexData: Data(repeating: 0x19, count: 32))
+        let transport = MockTransport()
+        transport.connectedPeers.insert(stablePeerID)
+        transport.securePeers = [stablePeerID]
+
+        let router = MessageRouter(transports: [transport])
+        router.sendPrivate("Hello", to: stablePeerID, recipientNickname: "Peer", messageID: "alias-retry")
+
+        router.retrySecurePrivateMessagesAfterAuthentication(for: [shortPeerID, stablePeerID, stablePeerID])
+
+        #expect(transport.sentPrivateMessages.map(\.messageID) == ["alias-retry", "alias-retry"])
+        #expect(transport.sentPrivateMessages.allSatisfy { $0.peerID == stablePeerID })
+    }
+
+    @Test @MainActor
+    func authenticationRetry_preservesFIFOAcrossSplitAliases() async {
+        let shortPeerID = PeerID(str: "0000000000000022")
+        let stablePeerID = PeerID(hexData: Data(repeating: 0x22, count: 32))
+        let transport = MockTransport()
+        transport.connectedPeers = [shortPeerID, stablePeerID]
+        transport.securePeers = [shortPeerID, stablePeerID]
+        let clock = MutableTestClock()
+        let router = MessageRouter(transports: [transport], now: { clock.now })
+
+        // The older message lives under the stable key, even though the auth
+        // callback supplies the ephemeral alias first.
+        router.sendPrivate("Older", to: stablePeerID, recipientNickname: "Peer", messageID: "fifo-old")
+        clock.now = clock.now.addingTimeInterval(1)
+        router.sendPrivate("Newer", to: shortPeerID, recipientNickname: "Peer", messageID: "fifo-new")
+        transport.resetRecordings()
+
+        router.retrySecurePrivateMessagesAfterAuthentication(for: [shortPeerID, stablePeerID])
+
+        #expect(transport.sentPrivateMessages.map(\.messageID) == ["fifo-old", "fifo-new"])
+        #expect(transport.sentPrivateMessages.map(\.peerID) == [stablePeerID, shortPeerID])
+    }
+
+    @Test @MainActor
+    func authenticationRetry_doesNotDuplicateNormalPendingHandshakeSend() async {
+        let peerID = PeerID(str: "0000000000000020")
+        let transport = MockTransport()
+        transport.connectedPeers.insert(peerID)
+        transport.securePeers = []
+
+        let router = MessageRouter(transports: [transport])
+        router.sendPrivate("Hello", to: peerID, recipientNickname: "Peer", messageID: "normal-handshake")
         #expect(transport.sentPrivateMessages.count == 1)
+
+        // BLE owns this pending send and drains it after authentication. Once
+        // the session becomes secure, the router's targeted auth retry must
+        // stay silent instead of producing a second copy.
+        transport.securePeers = [peerID]
+        router.retrySecurePrivateMessagesAfterAuthentication(for: [peerID])
+        #expect(transport.sentPrivateMessages.count == 1)
+
+        router.markDelivered("normal-handshake")
+    }
+
+    @Test @MainActor
+    func authenticationRetry_scopesCollidingMessageIDsByPeer() async {
+        let securePeer = PeerID(str: "0000000000000025")
+        let pendingPeer = PeerID(str: "0000000000000026")
+        let transport = MockTransport()
+        transport.connectedPeers = [securePeer, pendingPeer]
+        transport.securePeers = [securePeer]
+
+        let router = MessageRouter(transports: [transport])
+        let promotedID = "collision-promoted"
+        let clearedID = "collision-cleared"
+
+        // Pending B then secure A: an ID-global marker falsely promotes B.
+        router.sendPrivate(
+            "pending promoted",
+            to: pendingPeer,
+            recipientNickname: "Pending",
+            messageID: promotedID
+        )
+        router.sendPrivate(
+            "secure promoted",
+            to: securePeer,
+            recipientNickname: "Secure",
+            messageID: promotedID
+        )
+
+        // Secure A then pending B: an ID-global removal falsely clears A.
+        router.sendPrivate(
+            "secure cleared",
+            to: securePeer,
+            recipientNickname: "Secure",
+            messageID: clearedID
+        )
+        router.sendPrivate(
+            "pending cleared",
+            to: pendingPeer,
+            recipientNickname: "Pending",
+            messageID: clearedID
+        )
+
+        transport.resetRecordings()
+        transport.securePeers = [securePeer, pendingPeer]
+
+        router.retrySecurePrivateMessagesAfterAuthentication(for: [pendingPeer])
+        #expect(transport.sentPrivateMessages.isEmpty)
+
+        router.retrySecurePrivateMessagesAfterAuthentication(for: [securePeer])
+        #expect(transport.sentPrivateMessages.count == 2)
+        #expect(Set(transport.sentPrivateMessages.map(\.messageID)) == [promotedID, clearedID])
+        #expect(transport.sentPrivateMessages.allSatisfy { $0.peerID == securePeer })
+    }
+
+    @Test @MainActor
+    func authenticationRetry_doesNotDuplicateMessageRequeuedByBLEForHandshake() async {
+        let peerID = PeerID(str: "0000000000000021")
+        let transport = MockTransport()
+        transport.connectedPeers.insert(peerID)
+        transport.securePeers = [peerID]
+
+        let router = MessageRouter(transports: [transport])
+        router.sendPrivate("Hello", to: peerID, recipientNickname: "Peer", messageID: "session-lost")
+        #expect(transport.sentPrivateMessages.count == 1)
+
+        // The session disappears before a normal outbox flush. That send is
+        // now owned by BLE's pending-handshake queue, so it clears the
+        // router's secure-auth retry marker.
+        transport.securePeers = []
+        router.flushOutbox(for: peerID)
+        #expect(transport.sentPrivateMessages.count == 2)
+
+        transport.securePeers = [peerID]
+        router.retrySecurePrivateMessagesAfterAuthentication(for: [peerID])
+        #expect(transport.sentPrivateMessages.count == 2)
+
+        router.markDelivered("session-lost")
+    }
+
+    @Test @MainActor
+    func sendPrivate_fastDeliveryAckCannotRaceAheadOfRetention() async {
+        let peerID = PeerID(str: "0000000000000017")
+        let transport = MockTransport()
+        transport.connectedPeers.insert(peerID)
+        transport.securePeers = [peerID]
+
+        let router = MessageRouter(transports: [transport])
+        transport.onSendPrivateMessage = { messageID in
+            router.markDelivered(messageID)
+        }
+
+        router.sendPrivate("Hello", to: peerID, recipientNickname: "Peer", messageID: "fast-ack")
+        #expect(transport.sentPrivateMessages.map(\.messageID) == ["fast-ack"])
+
+        transport.onSendPrivateMessage = nil
+        router.flushOutbox(for: peerID)
+        #expect(transport.sentPrivateMessages.map(\.messageID) == ["fast-ack"])
+    }
+
+    @Test @MainActor
+    func flushOutbox_synchronousAckDoesNotResurrectSnapshotEntry() async {
+        let peerID = PeerID(str: "0000000000000018")
+        let transport = MockTransport()
+        transport.connectedPeers.insert(peerID)
+        transport.securePeers = [peerID]
+
+        let router = MessageRouter(transports: [transport])
+        router.sendPrivate("Hello", to: peerID, recipientNickname: "Peer", messageID: "flush-fast-ack")
+        transport.onSendPrivateMessage = { messageID in
+            router.markDelivered(messageID)
+        }
+
+        router.flushOutbox(for: peerID)
+        #expect(transport.sentPrivateMessages.count == 2)
+
+        transport.onSendPrivateMessage = nil
+        router.flushOutbox(for: peerID)
+        #expect(transport.sentPrivateMessages.count == 2)
     }
 
     @Test @MainActor
@@ -392,10 +605,31 @@ struct MessageRouterTests {
         #expect(transport.sentPrivateMessages.count == 11)
     }
 
-    /// With an established secure session the connected fast-path stays
-    /// exactly as before: trusted outright, no retained copy, no courier.
     @Test @MainActor
-    func sendPrivate_connectedWithSecureSessionIsTrustedOutright() async {
+    func authenticationRetry_capsActualSecureTransmissions() async {
+        let peerID = PeerID(str: "00000000000000ad")
+        let transport = MockTransport()
+        transport.connectedPeers.insert(peerID)
+        transport.securePeers = [peerID]
+
+        let router = MessageRouter(transports: [transport])
+        var dropped: [String] = []
+        router.onMessageDropped = { messageID, _ in dropped.append(messageID) }
+
+        router.sendPrivate("Hello", to: peerID, recipientNickname: "Peer", messageID: "secure-retry")
+        for _ in 0..<10 {
+            router.retrySecurePrivateMessagesAfterAuthentication(for: [peerID])
+        }
+
+        #expect(dropped == ["secure-retry"])
+        #expect(transport.sentPrivateMessages.count == 8)
+    }
+
+    /// With an established secure session the connected fast-path sends
+    /// immediately and never leaks to couriers, but retains a local encrypted
+    /// outbox copy until the peer confirms receipt.
+    @Test @MainActor
+    func sendPrivate_connectedWithSecureSessionRetainsLocallyWithoutCourier() async {
         let peerID = PeerID(str: "00000000000000ab")
         let peerKey = Data(repeating: 0xAB, count: 32)
         let courier = PeerID(str: "00000000000000cc")
@@ -415,7 +649,11 @@ struct MessageRouterTests {
         #expect(transport.sentPrivateMessages.map(\.messageID) == ["cs2"])
         #expect(transport.sentCourierMessages.isEmpty)
         router.flushOutbox(for: peerID)
-        #expect(transport.sentPrivateMessages.count == 1)
+        #expect(transport.sentPrivateMessages.count == 2)
+        #expect(transport.sentCourierMessages.isEmpty)
+        router.markDelivered("cs2")
+        router.flushOutbox(for: peerID)
+        #expect(transport.sentPrivateMessages.count == 2)
     }
 
     @Test @MainActor
@@ -527,6 +765,52 @@ struct MessageRouterTests {
         #expect(carried == ["bridge-ack"])
     }
 
+    @Test @MainActor
+    func bridgeDepositsScopeCollidingMessageIDsByRecipient() async {
+        let firstRecipient = PeerID(str: "00000000000000b1")
+        let secondRecipient = PeerID(str: "00000000000000b2")
+        let firstKey = Data(repeating: 0xB1, count: 32)
+        let secondKey = Data(repeating: 0xB2, count: 32)
+        let recipientKeys = [
+            firstRecipient: firstKey,
+            secondRecipient: secondKey
+        ]
+        let router = MessageRouter(
+            transports: [MockTransport()],
+            courierDirectory: CourierDirectory(
+                noiseKey: { recipientKeys[$0] },
+                isTrustedCourier: { _ in false }
+            )
+        )
+        var requestedKeys: [Data] = []
+        var completions: [@MainActor (Bool) -> Void] = []
+        router.bridgeCourierDeposit = { _, _, recipientKey, completion in
+            requestedKeys.append(recipientKey)
+            completions.append(completion)
+        }
+        var carriedPeers: [PeerID] = []
+        router.onMessageCarried = { _, peerID in carriedPeers.append(peerID) }
+
+        router.sendPrivate(
+            "First",
+            to: firstRecipient,
+            recipientNickname: "First",
+            messageID: "bridge-collision"
+        )
+        router.sendPrivate(
+            "Second",
+            to: secondRecipient,
+            recipientNickname: "Second",
+            messageID: "bridge-collision"
+        )
+
+        #expect(completions.count == 2)
+        #expect(Set(requestedKeys) == [firstKey, secondKey])
+
+        completions.forEach { $0(true) }
+        #expect(Set(carriedPeers) == [firstRecipient, secondRecipient])
+    }
+
     // MARK: - Outbox persistence
 
     @Test @MainActor
@@ -582,6 +866,82 @@ struct MessageRouterTests {
         #expect(transport2.sentPrivateMessages.isEmpty)
     }
 
+    @Test @MainActor
+    func scopedDeliveryAckClearsOnlySelectedPeerWhenMessageIDsCollide() async {
+        let fileURL = FileManager.default.temporaryDirectory
+            .appendingPathComponent("router-outbox-scoped-ack-\(UUID().uuidString).sealed")
+        defer { try? FileManager.default.removeItem(at: fileURL) }
+        let keychain = MockKeychain()
+        let acknowledgedPeer = PeerID(str: "00000000000000d1")
+        let otherPeer = PeerID(str: "00000000000000d2")
+        let transport = MockTransport()
+        let router = MessageRouter(
+            transports: [transport],
+            outboxStore: MessageOutboxStore(keychain: keychain, fileURL: fileURL)
+        )
+        router.sendPrivate("For acknowledged peer", to: acknowledgedPeer, recipientNickname: "One", messageID: "shared-id")
+        router.sendPrivate("For other peer", to: otherPeer, recipientNickname: "Two", messageID: "shared-id")
+
+        #expect(router.markDelivered("shared-id", for: [acknowledgedPeer]))
+        transport.reachablePeers.formUnion([acknowledgedPeer, otherPeer])
+        router.flushOutbox(for: acknowledgedPeer)
+        router.flushOutbox(for: otherPeer)
+
+        #expect(transport.sentPrivateMessages.map(\.peerID) == [otherPeer])
+        let persisted = MessageOutboxStore(keychain: keychain, fileURL: fileURL).load()
+        #expect(persisted[acknowledgedPeer] == nil)
+        #expect(persisted[otherPeer]?.map(\.messageID) == ["shared-id"])
+    }
+
+    @Test @MainActor
+    func scopedAckWhileColdLoadIsLockedPreventsOnlyTargetPeerResurrection() async {
+        let fileURL = FileManager.default.temporaryDirectory
+            .appendingPathComponent("router-locked-scoped-ack-\(UUID().uuidString).sealed")
+        defer { try? FileManager.default.removeItem(at: fileURL) }
+        let keychain = MockKeychain()
+        let acknowledgedPeer = PeerID(str: "00000000000000d3")
+        let otherPeer = PeerID(str: "00000000000000d4")
+        let durable = MessageOutboxStore.QueuedMessage(
+            content: "Queued before reboot",
+            nickname: "Peer",
+            messageID: "shared-locked-id",
+            timestamp: Date()
+        )
+        MessageOutboxStore(keychain: keychain, fileURL: fileURL).save([
+            acknowledgedPeer: [durable],
+            otherPeer: [durable]
+        ])
+
+        var protectedDataUnavailable = true
+        let restoredStore = MessageOutboxStore(
+            keychain: keychain,
+            fileURL: fileURL,
+            readData: { url in
+                if protectedDataUnavailable {
+                    throw NSError(domain: NSCocoaErrorDomain, code: NSFileReadNoPermissionError)
+                }
+                return try Data(contentsOf: url)
+            }
+        )
+        let transport = MockTransport()
+        transport.reachablePeers.formUnion([acknowledgedPeer, otherPeer])
+        let router = MessageRouter(transports: [transport], outboxStore: restoredStore)
+
+        router.markDelivered(
+            "shared-locked-id",
+            from: [acknowledgedPeer]
+        )
+        protectedDataUnavailable = false
+        restoredStore.retryDeferredLoad()
+        await Task.yield()
+        await Task.yield()
+
+        #expect(transport.sentPrivateMessages.map(\.peerID) == [otherPeer])
+        let persisted = MessageOutboxStore(keychain: keychain, fileURL: fileURL).load()
+        #expect(persisted[acknowledgedPeer] == nil)
+        #expect(persisted[otherPeer]?.map(\.messageID) == ["shared-locked-id"])
+    }
+
     @Test @MainActor
     func protectedDataRecoveryMergesDurableAndLockedWakeMessagesIntoRouter() async {
         let fileURL = FileManager.default.temporaryDirectory
@@ -780,12 +1140,14 @@ struct MessageRouterTests {
         protectedDataUnavailable = false
         restoredStore.retryDeferredLoad() // captures unseen durable + known wake
 
-        // Secure direct flush removes the wake message before recovery's
+        // A secure direct retry followed by its delivery ack removes the wake
-        // MainActor merge. It must remain removed, while the unseen durable
+        // message before recovery's MainActor merge. It must remain removed,
-        // message still arrives through the pending recovery claim.
+        // while the unseen durable message still arrives through the pending
+        // recovery claim.
         transport.connectedPeers.insert(peerID)
         transport.securePeers = [peerID]
         router.flushOutbox(for: peerID)
+        router.markDelivered("recovery-gap-known")
         await Task.yield()
         await Task.yield()
 
@@ -856,7 +1218,8 @@ struct MessageRouterTests {
         restoredStore.retryDeferredLoad() // persists D+W and queues recovery
         transport.connectedPeers.insert(peerID)
         transport.securePeers = [peerID]
-        router.flushOutbox(for: peerID) // removes W before queued callback
+        router.flushOutbox(for: peerID)
+        router.markDelivered("recovery-write-failure-known") // removes W before queued callback
 
         // The gap save may remove W, but it must leave unseen D durable until
         // MessageRouter receives the pending recovery callback.

bitchatTests/ViewSmokeTests.swift

@@ -551,6 +551,89 @@ struct ViewSmokeTests {
         #expect(featureModels.privateConversationModel.selectedHeaderState?.headerPeerID == peerID)
     }
 
+    @Test("Root Bluetooth alert waits for location and notices sheets")
+    func rootBluetoothAlertGuard_includesHeaderSheets() {
+        #expect(!ContentRootModalPresentationState().hasPresentation)
+        #expect(
+            ContentRootModalPresentationState(
+                isLocationChannelsSheetPresented: true
+            ).hasPresentation
+        )
+        #expect(
+            ContentRootModalPresentationState(
+                isNoticesSheetPresented: true
+            ).hasPresentation
+        )
+    }
+
+    @Test("People-sheet Bluetooth alert waits for local verification sheet")
+    func peopleSheetBluetoothAlertGuard_includesVerificationSheet() {
+        #expect(!ContentPeopleSheetModalPresentationState().hasPresentation)
+        #expect(
+            ContentPeopleSheetModalPresentationState(
+                isVerificationSheetPresented: true
+            ).hasPresentation
+        )
+    }
+
+    @Test("Root Bluetooth alert waits for screenshot privacy alert")
+    @MainActor
+    func rootBluetoothAlertGuard_tracksScreenshotPrivacyState() {
+        let (viewModel, _, _) = makeSmokeViewModel()
+        let featureModels = makeSmokeFeatureModels(for: viewModel)
+
+        #expect(
+            !ContentRootModalPresentationState(
+                appChromeModel: featureModels.appChromeModel
+            ).hasPresentation
+        )
+
+        featureModels.appChromeModel.showScreenshotPrivacyWarning = true
+
+        #expect(
+            ContentRootModalPresentationState(
+                appChromeModel: featureModels.appChromeModel
+            ).hasPresentation
+        )
+    }
+
+    @Test("People-sheet Bluetooth alert waits for legacy media consent")
+    @MainActor
+    func peopleSheetBluetoothAlertGuard_tracksLegacyConsentState() async {
+        let (viewModel, _, _) = makeSmokeViewModel()
+        let featureModels = makeSmokeFeatureModels(for: viewModel)
+
+        #expect(
+            !ContentPeopleSheetModalPresentationState(
+                legacyPrivateMediaConsentRequest:
+                    featureModels.conversationUIModel
+                        .legacyPrivateMediaConsentRequest
+            ).hasPresentation
+        )
+
+        viewModel.enqueueLegacyPrivateMediaConsent(
+            for: PeerID(str: "5152535455565758"),
+            transferId: "legacy-consent-transfer",
+            messageID: "legacy-consent-message"
+        ) { _ in }
+        defer { viewModel.cancelAllLegacyPrivateMediaConsents() }
+
+        let consentPropagated = await TestHelpers.waitUntil {
+            featureModels.conversationUIModel
+                .legacyPrivateMediaConsentRequest != nil
+        }
+        #expect(
+            consentPropagated
+        )
+        #expect(
+            ContentPeopleSheetModalPresentationState(
+                legacyPrivateMediaConsentRequest:
+                    featureModels.conversationUIModel
+                        .legacyPrivateMediaConsentRequest
+            ).hasPresentation
+        )
+    }
+
     @Test
     func geohashAndTextMessageViews_renderCoreBranches() {
         let (viewModel, _, _) = makeSmokeViewModel()