Connections to server maintained also when offline
With EWS account with calendars, when Evolution is set to offline mode, connections to EWS servers remain open:
$ netstat -tapn|grep evo
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
tcp 0 0 192.168.1.222:58446 40.101.65.226:443 ESTABLISHED 15189/evolution-calendar-factory
tcp 0 0 192.168.1.222:58412 40.101.65.226:443 ESTABLISHED 15201/evolution-source-registry
tcp 0 0 192.168.1.222:55894 40.101.126.210:443 ESTABLISHED 15189/evolution-calendar-factory
Presumably, EWS should honor the offline/online setting and not maintain a persistent connection.