Jack is in the banking industry and he recently left his job. But when he did, he lost his Apple ID and they remote wiped his phone. Will he have trouble switching it over to a new Apple ID and will he lose all the apps, music, etc. that he bought? Leo says that Jack should be able to go to the Apple ID and change the email associated with it. They'll look for confirmation on the old email, though. He'll need to also log into the old Apple ID account and turn off Find My iPhone and back up to iCloud.
Leo says that he'll need to contact Apple and see what they can do. They have the keys to the kingdom. All he needs to do is prove he is who he says he is, and they'll free it up. Macworld has an article on how to change the ID email without access to the old account here.