I just completed, or thought that I had completed, migrating all mailboxes from our 2010 > 2013 CU9 environment. I have noticed that there are multiple system mailboxes and only one was moved over during migration. We have issues occurring in our new environment such as not being able to do eDiscovery. I have all system mailboxes now copied over to 2013, but before I complete the move request, I just want to make sure that there will be no negative impact during business hours, or if I should wait until after hours to complete the request. Any info would be greatly appreciated.