In order to make CMN FB to use the "Autodiscover Endpoint" follow below steps:
1. Close the CMN console.
2. Open via notepad the following config file:
C:\Program Files (x86)\Dell\Coexistence Manager for Notes\Free Busy Connector\ExchangeFreeBusyService\ExchangeFreeBusyService.exe",
3. Remove the value of app settings key "ExchangeEwsUrl":
4. Reopen the CMN console.
Verified by the Dev team has a bug (#663283). There is not ETA available yet for this fix to be released..