push_route_registration_rate_limited· reason_code· applies to service_callInternal audit reason recorded when push-route registration / rotation writes for a `(recipient_id, principal_id, device_id)` exceed the default rate (8 writes per 60s). The outward response uses a generic rate-limited envelope; this reason is for server-side abuse detection only. See zh/crypto-media/device-lifecycle.md §5.6.2 and zh/conformance/scalability-constraints.md §6.1.