DefaultServices.updateInstance() rejects plan updates despites plan is updateable.

The OSB API states regarding a service offering metadata that its updateable flag can be overriden in plans.

https://github.com/openservicebrokerapi/servicebroker/blob/master/spec.md#service-offering-object

Response Field	Type	Description
[...]
plan_updateable	boolean	Whether the Service Offering supports upgrade/downgrade for Service Plans by default. Service Plans can override this field (see Service Plan). Please note that the misspelling of the attribute plan_updatable as plan_updateable was done by mistake. We have opted to keep that misspelling instead of fixing it and thus breaking backward compatibility. Defaults to false.

https://github.com/openservicebrokerapi/servicebroker/blob/master/spec.md#service-plan-object

Response Field	Type	Description
[...]
plan_updateable	boolean	Whether the Plan supports upgrade/downgrade/sidegrade to another version. This field is OPTIONAL. If specificed, this takes precedence over the Service Offering's plan_updateable field. If not specified, the default is derived from the Service Offering. Please note that the attribute is intentionally misspelled as plan_updateable for legacy reasons.

Unfortunately the CC API reuses the two fields, but isn't precise enough to state that plan.updateable override serviceoffering.plan_updateable

https://apidocs.cloudfoundry.org/12.42.0/services/retrieve_a_particular_service.html

Name	Description	Default	Valid Values	Example Values
plan_updateable	A boolean describing that an instance of this service can be updated to a different plan	false

https://apidocs.cloudfoundry.org/12.42.0/service_plans/retrieve_a_particular_service_plan.html

"plan_updateable": true,

As a result, cf-java-client refuses service instance updates unless the service definition is updateable, regardless than the service plan is updateable.

https://github.com/cloudfoundry/cf-java-client/blob/8ec06b4cdd61dda0f0ba5e4d546651b880735faa/cloudfoundry-operations/src/main/java/org/cloudfoundry/operations/services/DefaultServices.java#L515-L517

Given that CloudFoundry itself likely performs the checks, is there any reason to also perform the check client-side ?

If there is a good reason, then the logic should be fixed to only reject when both serviceplan.plan_updateable=false and servicedefinition.plan_updateable=false

Start at cloudfoundry-operations/src/main/java/org/cloudfoundry/operations/services/DefaultServices.java lines 515-517 and compare the service definition and service plan updateability fields against the linked OSB and Cloud Foundry API definitions. Review the existing service instance update flow and its tests, if present. Done means valid plan updates are no longer rejected solely because the service definition is not updateable.