I would contact Apple and ask them. Lawrence is correct that AppleCare+ is on the device, but I am concerned that if you are changing carriers and you pay the carrier directly for AppleCare+ that when you no longer are paying that carrier, your AppleCare+ plan may not continue.
I have an AppleCare+ plan for my MacBook Pro, but it is paid through BestBuy. I asked Apple if I could pay for it through Apple directly and Apple told me I could not do that. If I wanted to keep the plan, I had to continue paying BestBuy for it.