Yes, you may request that your billing date be changed. When you do, however, the system can not prorate any balance that might be reflected by that new date. If you are billed on the 8th of each month, for example, and you would like to change it to the 4th, you will be billed for the entire next billing period on the 4th, even though, technically, you would have already paid through the 8th of the current billing cycle.