Multiple VIP EG servers where one or more keep switching to Automatic Business Continuity mode and don't switch back. The servers communicate to Symantec cloud through proxies, but even after removing the proxies, the behavior persists.
The servers in question go through a different network route for which there is no firewall rules are setup. The Automatic Business Continuity mode validation server performs a plain HTTP connect on port 443, which needs to be allowed in the firewall/proxy rules.
Add firewall rules for the failed servers, that should address this.