I bought my iPhone 6 64 GB on ATT Next last year on release day. I still have $330 or so left to pay off. My question is would you pay the rest off so i can keep the phone or use another line's ATT Next upgrade then do the switch. I guess in the end it doesn't really matter but i was thinking of paying it off so I don't have to deal with going into the ATT store on launch day to do the sim switch or whatever.