I have T-Mobile jump. And the way it works is if you pay half of the phone off they will pay the remaining balance of your EIP so that you can upgrade... I paid off half of it in less than a year with regular payments.... so when this one comes out I'm gonna get it... and by next year I will be able to jump again to the new iPhone if I want... unless the upgrade isn't worth it the. I'll just pay off the phone all the way and keep itYou either Pay off the remaining EIP balance or keep making EIP payments.