SEP (Symantec Endpoint Protection) for Mac does not use location-specific communication settings; if you configure SEP for Mac to use location-awareness and to use a customized list of SEPM servers (MSL, or Management Server List) when in a certain location, the client will continue communicating with the group-level MSL rather than the location-specific MSL.
Symantec is aware of this issue and is investigating. This article will be updated as new information becomes available.
SEP for Mac
To work around this problem, be sure to specify all possibly-available SEPMs in the group-level communications settings. Be also aware that SEP for Mac will ignore any location-specific communication settings (MSL, heartbeat, etc) and use only the group-level communication settings.