I ordered an iPhone 6+ 64Gb, Silver on Apple.com using AT&T Next.
Suppose I see a 128 gb at the local store, can I cancel my online order right before I walk into the store and use ATT Next to buy the 128 gb 6+?
If it's at Apple, no. The apple store does not do att next.
If you see one at att, yes. I read it takes 5-10 minutes for the upgrade to return to the account once the order us cancelled.