I have an O365 account with 80 mailboxes that I need to migrate from tenant1 to tenant2
Only Exchange Online is beeing used, no SharePoint, no Office online
Microsoft domain in tenant1 is tenant1.onmicrosoft.com
company domain is acme.com
Mail accounts are email@example.com
Microsoft domain in tenant2 is tenant2.onmicrosoft.com
company domain will be acme.com
Mail accounts will be firstname.lastname@example.org
I have to migrate acme.com (and all email addresses email@example.com) from MS tenant1 to MS tenant2
80 emails addresses firstname.lastname@example.org are in use and "down time" has to be minimum
I noticed that I cannot even register acme.com in MS tenant2 without deleting acme.com from MS tenant1.
When I change DNS in acme.com for tenant2 it tells me that acme.com is already registered in tenant1...and that I need to "delete" acme.com from tenant1....
I only use Exchange Online (80 mailboxes). No SharePoint, No office online applications
What is the good procedure to migrate from tenant1 to tenant2 ?
How do I delete acme.com from tenant1 since all mailboxes are configured with acme.com? Manually? non automatic procedure?