Yesterday I purchased a 4s from AT&T online. The confirmation indicated, as expected, that there would be a one month delay in shipment. I was told that there are some 4s in stock at a few local AT&T stores. If I go to an AT&T store, say, today, can I purchase it through the store without any penalty from purchasing online? In other words, can I purchase through the store today and have my online order cancelled?