Google Apps Users that have other user calendars in their My Calendars will have a copy in their Target inbox after migration (149446)

This behavior is by design

Is the additional calendar is not needed, users need either to manually remove the shared calendars on the target after migration, or follow the steps below prior to migration to change the Sharing Permission Settings

1. Log in to the account whose calendar is being shared
2. Go to Calendar | Settings (gear icon) | Settings | Calendars
3. Click on sharing for the desired calendar
4. Under Share with specific people change the Permission Settings for the user(s) with the “Make changes AND manage sharing” permission to any other option you want.
5. Save

Organization-wide

1. Log in to the Organization admin account
2. From the Admin Console, click on Google Apps
3. Click on the Calendar service
4. Click on Sharing settings

5. Under External Sharing options for primary calendars ensure that Share all information and Allow Managing of Calendars are not selected