Uh, these days that isn't the way Dish does it. When did they change to the current way, which is to get the first bill paid with order and then the next bill is for the month. IOW, only one month's charge at a time.
Well it's not always a full month, but Dish has a billing schedule and depending on when you start your service, the first bill could be almost two months of charges. Check out channel 101 at :24 and :54 past the hour for an explanation.