According to How Symantec Endpoint Protection (SEP) client load balancing works in a managed environment, setting the described registry value UseLastServer=0 will direct the SEP client to randomly pick a management server from multiple choices. As of SEP version 14.2, this does not appear to be working - the client always chooses the first available server.
The first phase of this issue has been addressed in SEP 14.2 RU1 (14.2.3332.1000)
The second phase of this issue will be resolved in the upcoming SEP 14.2 RU1 MP1 (build number TBD)
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