The new default value for com.openexchange.hazelcast.maxOperationTimeout in the configuration file hazelcast.properties will be changed from the previous default of 5000 (5 seconds) to 30000 (30 seconds):

# Specifies the implicit maximum operation timeout in milliseconds for
# operations on distributed data structures, if no explicit timeout is
# specified for an operation. Defaults to 30000.
com.openexchange.hazelcast.maxOperationTimeout=300 00