Hi--I purchased my iPhone 6s Plus last year when ATT was still offering the two year subsidized contracts. It doesn't actually expire until Sept 2017. I should be able to sell the phone to an ATT user correct? Does this mean the phone is actually still "on contract" until Sept 2017 and not just "locked" to ATT? Or does this mean the same thing? Just want to make sure my listing on EBay is correct in terminology. thanks!