Migration

Move live traffic onto prepaid without naming rails

Cutover onto IOSOR prepaid without naming the pipes you leave. Map spend, rotate keys, and rewrite buyer copy before Live volume moves.

Dual-write window risk during cutover

Two webhooks for one message is a debit and DLR hazard. Cap the dual-write window, dedupe money events, and exit with one ledger owner.

Old webhooks must drain before you cut keys

Drain in-flight DLR on the old endpoint before you revoke keys. Cut only after quiet, then re-prove day-1 runway and ordered failover.