Unable to associate a storage area with a storage policy when the number of subscribed events exceeds the number of subscription cache entries

Symptom

Error returned in ACCE:
FNRAC1005E
The '<Storage Policy Name>' object was not saved.
User response: Refresh the object, reenter your changes, and try again, or contact your system administrator.
Exception details:
An unexpected exception occurred. The unexpected exception is chained to this exception. Message was: null

Error in the CPE p8_server_error.log:
2017-08-30T09:10:06.830 5066AEAF ERR FNRCE0066D - DEBUG com.filenet.api.exception.EngineRuntimeException: FNRCE0066E: E_UNEXPECTED_EXCEPTION: An unexpected exception occurred. The unexpected exception is chained to this exception. Message was: null
at com.filenet.engine.jca.impl.RequestBrokerImpl.executeChanges(RequestBrokerImpl.java:1363)
at com.filenet.engine.jca.impl.RequestBrokerImpl.executeChanges(RequestBrokerImpl.java:1190)
at com.filenet.engine.ejb.EngineCoreBean._executeChanges(EngineCoreBean.java:618)
at com.filenet.engine.ejb.EngineCoreBean.executeChanges(EngineCoreBean.java:586)
at com.filenet.engine.ejb.EJSLocalStatelessEngineCore_22877cb1.executeChanges(Unknown Source)
at com.filenet.engine.ejb.EngineBean.executeChanges(EngineBean.java:832)
at com.filenet.apiimpl.transport.ejbstubs.EJSRemoteStatelessEngine_2e64c374.executeChanges(Unknown Source)
at com.filenet.apiimpl.transport.ejbstubs._Engine_Stub.executeChanges(_Engine_Stub.java:671)
at com.filenet.apiimpl.transport.ejb.EJBSession$EJBImpl._executeChanges(EJBSession.java:861)
at com.filenet.apiimpl.transport.ejb.EJBSession$EJBImpl.executeChanges(EJBSession.java:602)
at com.filenet.apiimpl.transport.ejb.EJBSession.executeChanges(EJBSession.java:393)
at com.filenet.apiimpl.util.SessionHandle.executeChanges(SessionHandle.java:112)
at com.filenet.apiimpl.core.Session.callExecuteChanges(Session.java:151)
at com.filenet.apiimpl.core.Session.executeChanges(Session.java:527)
at com.filenet.apiimpl.core.Session.executeChange(Session.java:830)
at com.filenet.apiimpl.core.IndependentlyPersistableObjectImpl.save(IndependentlyPersistableObjectImpl.java:86)
at com.filenet.apiimpl.core.IndependentlyPersistableObjectImpl.save(IndependentlyPersistableObjectImpl.java:77)
...
Caused by: java.lang.NullPointerException
at com.filenet.engine.dbpersist.DBResult.nextRow(DBResult.java:261)
at com.filenet.engine.queueitem.SubscriptionProcessor.postProcessSubscriptions(SubscriptionProcessor.java:571)
at com.filenet.engine.persist.SubscribablePersister.postExecuteChange(SubscribablePersister.java:360)
at com.filenet.engine.persist.ReplicablePersister.postExecuteChange(ReplicablePersister.java:135)
at com.filenet.engine.persist.StoragePolicyPersister.postExecuteChange(StoragePolicyPersister.java:105)
at com.filenet.engine.persist.IndependentPersister.executeChangeWork(IndependentPersister.java:551)
at com.filenet.engine.persist.IndependentPersister.executeChange(IndependentPersister.java:334)
at com.filenet.engine.persist.SubscribablePersister.executeChange(SubscribablePersister.java:176)
at com.filenet.engine.jca.impl.RequestBrokerImpl.executeChanges(RequestBrokerImpl.java:1332)
... 67 more