Hi - I'm in the process of migrating multiple small business clients to Exchange Online.

Each migrated user will actually start with a trial version of E3, but they actually only need the Exchange Online Plan 1.

So, the process I'll follow is this:

1. set up users (with trial E3 licences)
2. migrate user accounts to Exchange Online
3. check that the migrations have been successful
4. purchase Exchange Online Plan 1 licences
5. apply Exchange Online Plan 1 licences to users
6. remove trial E3 licences from users

Basically, steps 5/6 involve switching licences - but when this happens, do mailboxes and all items remain intact? Or do they get wiped, meaning I need to migrate again?

Does that make sense?

They will not be wiped - even if you remove all licenses from a user, the mailbox will stay for 30 days. It will get disconnected though, so the best way to do steps 5/6 is to NOT press the save/confirm button in between. Go to the user settings page, licenses, remove the E3 license, add the EO Plan 1 license, and only then press the button.

Otherwise, you might have to wait for a bit for the mailbox to be accessible after you apply the new license.

And be sure not using features from Exchange plan 2. Like archiving and inplace hold. Kind regards joran