Farm deployment through Profile Service API prevents new members from joining cluster

Issue

Deploying Web Applications (WARs) to a cluster farm via either the EAP Administration Console or JBoss Operations Network caused a NullPointerException on the joining node, similar to the following:

16:16:53,586 ERROR [ScopedProfileServiceController] Error installing to Create: name=ProfileKey@27905a42[domain=default,server=default, name=farm] state=Configured mode=On Demand requiredState=Installed
java.lang.reflect.InvocationTargetException
...
Caused by: java.lang.NullPointerException
at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:796)
at org.jboss.ha.timestamp.TimestampDiscrepancyService.getTimestampDiscrepancy(TimestampDiscrepancyService.java:328)
at org.jboss.profileservice.cluster.repository.DefaultSynchronizationPolicy.getTimestampDiscrepancy(DefaultSynchronizationPolicy.java:158)
at org.jboss.profileservice.cluster.repository.DefaultSynchronizationPolicy.acceptUpdate(DefaultSynchronizationPolicy.java:121)