Anyone traded in a grace period iPhone 2G?

Hey all,
My father's BB Pearl broke on May 30th and he went out and miraculously found a NIB 8GB iPhone 2G at the local AT&T store. Since this is within the grace period, I should be able to walk in with his phone, have them hand me a 8GB iPhone 3G, and credit the CC with the $200 difference, correct?

Has anyone been through this ordeal yet? I'm looking for any official documentation of this policy as I'm sure the people at the AT&T store will fight me tooth and nail on this matter.

Thanks in advance!

While that's a great option (its how I upgraded to a 16GB iPhone 3G with money in my pocket), it's not really practical as my dad is not very tech savvy and doesn't want to switch to yet another system while I hunt for a new iPhone for him.


Anyone done the free grace period upgrade?