I have set up a directory synchronization between Azure and my Active Directory, have validated my custom domains and now I would like to setup a hybrid Exchange migration to Office 365. I have a separate account to manage Office 365.
One of the prerequisites is a domain validation in Office 365. Doing so result in an error since my domains are already validated in Azure.
Should I move all my resources to the Office 365 directory ? This seems not possible, so I guess I would have to restart the setup (App Services, SQL DB...) from the beginning ?
I guess I don't do this in the right way. Could someone light my way ?
EDIT : Office 365 is used by a very small percentage of my users for now (which are new users), 20 on ~3500. The others are still working with Exchange 2013. I would like to plan a migration in batch.