I believe you can request Microsoft Support to move the BC environment(s) from one tenant to another.
Request to move an environment
As a partner, you can submit a support request to Microsoft Support by following the guidance at Escalating support issues to Microsoft. When submitting these support requests, you must provide the following information:
- Proof of your delegated admin rights in both Azure AD tenants
- Confirmation from the customer that the environment move is authorized by them
You can request to move one or more environments. For Microsoft to do the move, you'll need to provide information about the source and destination Azure AD tenants, such as:
- Environments name, type and country
- Source tenant ID and domain
- Destination tenant ID and domain
- Does the destination tenant have a valid Business Central subscription?
- Does the destination tenant have enough available user licenses?
- Does the destination tenant have enough environment licenses?
- Does the destination tenant have enough storage available for the environments being migrated?
Once the move is completed, your environments will appear in your new tenant.
Considerations
- Environment data will remain unchanged during the move operation. The exact same environment will be linked to a specified Azure AD tenant.
- The country, Azure region, and type of the environment (production or sandbox) will remain the same, and can't be changed during this operation.
- The operation will involve a downtime period for the environment being moved (typically not exceeding 2 hours). So the operation needs to be coordinated with the customer and Microsoft Support.
- Business Central Support doesn't provide help with moving the Business Central subscriptions, domains, and other resources between the Azure AD tenants. Your support representative or account manager will assist you in contacting billing to cancel or credit your previous subscription, if needed.
docs.microsoft.com/.../tenant-admin-center-environments-move
