So my buddy just asked a good question that I need help answering. He has an iPhone XS max on ATT NEXT and still has a few payments left on it, he was thinking of trading in his iPhone XS to Apple to get the iPhone 11 and just continue to making payments on his XS max on his ATT bill. I know other trade ins places like swappa require the device to be paid off completely before you can trade in but I've looked on Apple site and read the FAQ and couldn't find anything about trading in a device that still on a payment plan. Does Apple allow this or will he have to pay off his iPhone on ATT next first?