Hi everyone, I ordered a 32GB wi-fi+3g model, but after a while I realized the 100$ for 64GB is worth it. However, didn't want to cancel it because pre-orders got pushed to June 7th. Now can I take my online order and swap it at an Apple Store or do I have to mail it back and wait? If so, I got it as a gift with my uncle's credit card, but he shipped it to me, can I just swap it and then pay the extra myself? Thanks.