Apple support doesn't know a thing anyway - I asked about what happens if I don't return my wife's old phone on iUP (since only the 24th payment is left) and they were like "oh, you have to trade in a phone." Meanwhile, in the FAQs - it says if you don't return a phone, the payments will just continue on that phone and your new phone. When I showed them that, they were just like ohhh you're right lol