Right, `registration_access_token` is expired together with client. If update/rotation is really needed the workaround can be update `registration_access_token` via Dynamic Registration Custom Script during update.
E.g. https://github.com/GluuFederation/community-edition-setup/blob/79508122a7e37318e05a2a8f55d09278479e2718/static/extension/client_registration/SampleScript.py#L67
```
client.setRegistrationAccessToken("newtoken");
```