You won't find out what the AP discount is for that time period -- or if there even is one -- until much later this year. AP rates are released for specific time periods every now and then, not on a predicatable basis.
You can check out historic rates for that time period to kind of guess where you may fall, but you've got a long wait ahead of you for anything definitive.
Edited to add: Duh...I just re-read your post - you already knew that! Sorry!
Here is what I found (from Mousesavers.com):
Passholder discounts are currently available for check-ins through 4/13/06.
Travel dates: 1/10/06-1/15/06 and 2/5/06-2/15/06. Discounts are $20 off Value resorts, $40 off Moderate resorts and $70 off Deluxe resorts. Book by 2/15/06. Use code EZA.
Travel dates: 1/16/06-2/4/06. Discounts are $30 off Value resorts, $60 off Moderate resorts and $96 off Deluxe resorts. Book by 2/4/06. Use code BKE.
Travel dates: 2/16/06-4/13/06. Discounts are $35 off Value resorts, $66 off Moderate resorts and $133 off Deluxe resorts. Book by 4/8/06. Use code EZK