I ordered a iPhone 6 Plus with ATT online with my eligible upgrade. If I cancel my order whilst in line at ATT, will their computers show a "eligible upgrade" by time I get to a ATT rep at the store? It seems like a risky proposition but i am contemplating on doing it. My Pre-Order is showing that it is "backordered" and it will be 10/2 - 10/13 before shipping. What say you?