Hadn't seen that repo, really interesting find. Using undocumented Continuity fields for discovery is tempting but I wouldn't want to build on something Apple could break in any iOS update. I'm doing a GATT characteristic handshake with a session-derived service UUID for re-identification after address rotations. Takes a couple extra seconds on reconnect but at least it's stable. Those Continuity protocol docs are useful regardless though, good to understand what Apple is doing under the hood.