Yes but the new phone is going to be at a certain price with a two year contract. So the big question is do you get the new phone at the price with the two year contract or have to pay full retail?
my understanding of Costco's policy is that if you're beyond the standard 14 day VZW "opt-out" period the contract itself is not affected at all. You simply pay the difference and the contract remains the same.
you might want to clarify with the rep in the Costco kiosk to make sure.