Google Apps to Google Apps migration: will it move or copy mail transferred?

Question

I'm moving 8 users from one domain to another on Google Apps with the Migration tool that is available on the administration panel, but can't find information on this:

When migrating mail, will the migration process remove the email from the users at the old domain? or will it just copy the email to the new domain?

Answer 1

It copies the mail. You can stop and resume the process, and migrate again to recover any mail received while the process was active; it won't duplicate existing mail. You can also set the starting date from which the mail will be migrated.