Changes a registration's status, its subscribed event types, or both. An omitted field is left alone, so sending only status does not touch the subscriptions.
Subscriptions
An empty eventTypes array is not the same as omitting it. [] subscribes the registration to nothing while leaving it in place, which is distinct from deleting it.
Subscriptions are replaced wholesale, never merged, and take effect from that moment on. Past events are not backfilled.
Changing the destination
The URL is not updatable. Changing where events go is a delete and a fresh registration, which yields a new identifier and a new secret.
Status and suspension
SUSPENDED cannot be requested; the platform sets it after repeated delivery failures. Setting ACTIVE clears both the suspension timestamp and the failure count, whatever the previous status was.

