In Macquarie, for Pega BPM Hazlecast version is 3.4.1. On 14th of May, Faced an issue for one of the service that - Case API calls reports SUCCESS with EMPTY <caseid> since approximately 8am on 14-May. we could see the Hazelcast exception i.e com.hazelcast.core.OperationTimeoutException in the logs in that duration, and Pega team recommended to upgrade the hazelcast version