I have a user that we created a Remote Mailbox in Exchange 2010 and after replication, it synced to Office 365. After the account synced, I assigned an E4 license to the user's account. Within a few hours, the user was no longer able to access his email from the client nor from webmail. I checked the user's license in Office 365 and the license had been removed and the user did not have any license assigned to his account. I, again, assigned an E4 license to the user and again, within a few hours, the license had removed itself. What the heck is going on?

Did you ever figure this one out? I've got an E3 user who's been working fine for months and now suddenly her license keeps being removed...