I switched from AT&T to Verizon, when the iPhone 4 rolled out on February 10th. We had two numbers on the AT&T account. My wife's 3G had no contract, so I switched her on February 10th and I switched my iPhone 4 after posting it on eBay on February 17th. I did not pay the AT&T bill that I received at the first of February because I knew that they advance billed. When I received my March bill I expected the February bill to be prorated but it was not. I called AT&T and talked to customer service and was told that because I canceled my account before the end of the billing cycle that my bill would not be prorated. My wife's number only used 2 days in the billing cycle and my number only used 10 days on the billing cycle. The advance bill was $129.62. I figured that it should have been prorated down to approximately $38.00. AT&T's policy is "When canceling an account at the end of the bill cycle, the customer will always receive a complete final bill with all usage charges and the monthly service charge. When service is canceled immediately, charges could possibly be prorated. Refer to Prorated Charges. Advanced Billing: Monthly recurring charges and airtime are not prorated even if the service is canceled before the bill cycle end date." I believe this is just another way for AT&T to take advantage of iPhone customer's that are tired of poor service and decided to switch to Verizon. I was willing to pay the early termination fee ($255.00 plus tax) but do not feel that I should have to pay for advance billed days that I did not use. I have filed a complaint with my state's utility commission. This looks like another class-action lawsuit for AT&T.