The mesh runs on the seat's bus alone (novox/hq ADR 0131, design 28 task 5.5). The host's old
dialling and enrolment paths are deleted with the switch that chose between them; a membership or
a token naming another bus is refused before anything is sent, rather than dialled on a transport
that no longer exists.
Step 3.5's first half, mirroring the controller's. A host says exactly two
things unprompted, and the difference between them is the whole interface:
a report must arrive, and a heartbeat must not be insisted on. So a report
goes through JetStream — it is the message the store-window guarantee is
about — and a heartbeat stays on core, because a heartbeat in a stream is
the mesh's least valuable message competing for retention with its most
valuable.
The host still imports nothing of the mesh's own (ADR 0005): this is its
own interface over its own libraries. It agrees with the controller because
a fixture holds both to one envelope, which is the only agreement that
survives two repositories.
Also recorded, where the next person reads it rather than in a plan: the
"newest wins" window narrows at the rollout and does not disappear. Last-
per-subject makes the catch-up half the stream's, and sequence orders them
definitively — but three pushes to a connected node are still three
deliveries. Saying which half goes is worth more than "can probably be
removed", which is how a load-bearing window gets deleted in a hurry.