DC rates are available, but in limited quantities. Last year there were AP rates, but you need to realize that 2001 was a very different year. Up until 2001, AP rates were not available in Oct, Nov and Dec as a rule. You can't count on them being available. *IF* they become available, you can probably look for them to come out in the September timeframe.
Your best plan is to book what you can afford right now. If a discount comes along, you can apply it to your current ressie, or if its' a good enough discount, upgrade to a better room/hotel.