design:
Exchange 2013 deployment on-prem including UM being used for UM for users. Domain and Exchange are set to companyA.net
companyA.com is set up in O365 for email\calendars etc.
ADFS and DirSync already configured to O365.
Available UPN's in AD are already companyA.com and companyA.net.
Plan:
Setup hybrid so some users can have mailboxes on-prem and others on O365.
Have companyA.com be the primary smtp address
Question:
1) The speech attendant part of UM on prem is a non-negotiable requirement. could the mailboxes be on O365 and still work correctly?
Other considerations:
1) Lync 2013 on-prem is deployed for all features including Enterprise voice. Presence, calendars, and voicemail from exchange required.
Need to have the MWI and calendaring\presence work.