When your father went into the store to get the device, was it a corporate store or one of the authorized retailers? Either way, if he is not authorized on the account then he knows your password and/or the last 4 of your ss number and that is how he got the upgrade. so.....no not legal but good luck getting anything done about it at this point.

When your note 3 was placed on your line it may have been coded (entered) incorrectly and changed your upgrade date. Is there a ETF associated with your line?

When you have an issue and need to talk to someone about your account, customer service is open from 7 AM to 11PM every day. most stores are open until 9PM weekdays. It's not feesable to hire a few hundred or thousand people for the purpose of answering email, no cellular company does this. The cost is just to high for no return.