As explained in move domain between office 365 tenants article, it is difficult to migrate a domain name from one Office 365 tenant to another.
This is because during such migration, the domain name could be unavailable for two days and mail delivery is affected during this time.
Fortunately, there is an alternative solution.
Cloudiway provides a mail routing platform that you can use to migrate domains between Microsoft 365 tenants
How does it work?
Cloudiway’s Mail Pouting platform routes email automatically from given domains to target domains.
You simply need to configure your inbound settings in the Mail Routing tool, and point your MX records to Cloudiway’s Mail Routing platform.
Mail routing is completely transparent and mail headers are not modified in any way.
Every time a mail arrives intended for bob@yourdomain.com, it will be delivered to bob@tenant2.onmicrosoft.com
When your domain is completely detached from your source tenant and you have reattached it to the target tenant and updated all recipients, users, groups, lists, etc., point your MX records to the target Office 365 tenant and stop using the Cloudiway mail routing platform.
How to activate this service
This service is not available by default, and has an additional cost. The setup and testing of the tool must be completed prior to your cutover. Our Consulting Services team will need at least 5 business day’s notice to schedule an initial setup call and discuss the cutover process. Please contact your Cloudiway Sales Manager for more information.