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It will take a few days (some say up to 7) but your upgrade date should reset and you should go back to your old contract.
 
Well, it depends on a couple of factors.

1. Are you a new AT&T Customer?
2. Do you want a different phone or do you just regret the purchase?
3. Did you port a number in from another Carrier?

Dave

It was an upgrade to an iPhone 3GS, so I probably had ~1 year left.

I am thinking of getting a Droid Super Incredible with front facing camera and a jetpack.
 
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