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**P1 — the binding proof was replayable onto another session.** The §4.5 verifier checklist omitted the check that the proof's noiseStaticPublicKey equals the remote static key the Noise session actually established. The proof is a self-contained signed blob with nothing tying it to the session it arrives on, so a peer M that had seen A's proof could replay it verbatim inside M's own session with B; B would verify A's signature, see a well-formed binding, and on first contact TOFU-pin A's signing key against M's fingerprint. Added as the first item in the checklist, with the attack written out, because "signed" and "bound to this conversation" are different properties and the difference is easy to lose in a bullet list. **announceV2 is 0x2C, not 0x05.** 0x05 only looks free. It has been recycled twice — announce, then bulkTransferResponse, then fragmentStart until #446 — so an old peer could still map it to a fragment header and misparse presence as a partial message. Values above voiceFrame = 0x29 have only ever been allocated forward, and 0x2A/0x2B belong to the courier spray-ack work, leaving 0x2C. Confirmed never used anywhere in this repository's history. **Outbound priority is now stated, not inherited.** announceV2 fell through to `default: .high`. High is the right answer — presence is small, time-bounded to its epoch and useless once stale — but for a type nothing emits yet, a fall-through means the choice gets made without anyone seeing it. **Reverted unexplained pbxproj churn.** Xcode had rewritten resource-phase ordering and dropped a share-extension entitlements membership exception; none of it belongs in this PR. The file now matches main byte for byte. **O7 said "payloads" where the arithmetic is over encoded frames.** The 241-256 / 497-768 / 1009-1792 ranges are what `pad` receives, which is the whole encoded packet, not the payload alone. **Added O9: a seized device recomputes every past peer ID.** K_rot is long-lived, so peerID_e is computable for any epoch by whoever holds it — someone who seizes a phone, or pulls the static key from a backup, can go back over historical radio captures and identify which were this device. Rotation defends against the passive observer, not against later key compromise. A hash ratchet would give forward secrecy for the ID stream at the cost of state that must survive restarts, tolerate clock jumps, and resynchronise after a gap — a real trade rather than an obvious win, so it is written down as a question rather than silently adopted. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>