Hi Arames,
The E-Mail Migration in the Exchange Control Panel is used for migrating mail from an on-premises messaging system to your cloud-based organization, it is not used for moving data or migrating between Office 365 mailboxes.
If you want to move data between Office 365 accounts, here is a related link: http://help.outlook.com/en-us/140/dd401503(d=loband).aspx?sl=1
Additionally, please post a new thread in this forum if you need further assistance for the Cutover Migration.
Thanks,
Bourne Zhang