I have an AD 2008 with Exchange 2010 setup in a LAB, along with an Office 365 Test LAB too. 3 users have been successfully synced using the AADS with Password Hash Sync. Teams, office etc works. Now at the stage of an Exchange Migration. Current setup is with a minimal Hybrid. Mailboxes are "on premise", user logs in fine sees mail etc. When assigned a license in O365 the user is assigned as a mailbox user rather than a mail user and therefore migration wont work. Duplicate mailboxes with 2 different guilds. I waited for ages before assigning "Exchange on-line" license. If anyone could point me in the right direction of what I am doing wrong I would be grateful.