b9vx3 (b9vx3) asked a question.
Changing login names without changing UPNs in AD
We are currently in an Office 365 hybrid deployment with profiles being mastered by AD. We recently acquired a new domain name and are working on a transition plan for moving from the old domain to the new one. The goal would be to give users the ability to sign in with user@new.com rather than user@old.com without changing the UPN that's still on the @old.com domain. Is there a way to specify an alternate login for users that will authenticate them in Okta as user@new.com but pass the correct authentication information to Office 365 as user@old.com? I've tried changing the UPN for a user and everything appears to work except mobile device email access, which is why I'd like to make this change without changing the UPN if possible.
