Placed an order with AT&T last week, but was able to reserve one at the Apple store tonight. I am doing an upgrade swap for my wife with my MIL's line on our account. Can I leave the Apple store tomorrow when I pick it up without activating it so I can take the phone and my wife's phone to the AT&T store to do the upgrade swap without screwing anything up? Ideally I don't want to have my MIL to have to do anything. 5 min of downtime for her is fine.