What is the longest date before the end of your contract that you can get a upgrade from cingular?

Answer 1

You can get a upgrade of your phone from Cingular from within 21 months of service with them which is 3 months prior to your ending of your 2 year contract. Cingular also looks at your payment history and any default payments that you have made to determine if you are eligible for a upgrade with a new phone.

Answer 2

After you end your contract, you will be paying month to month (just for the service)
by then Cingular will practically beg you to extend your contract, so, answering your question,
there is no "date"