AP discounts only come out a few months in advance of the time period. Your first AP or PAP is activated when you first use it. Then, if you get it renewed, it is renewed on the date of your first activation. We get the PAP and when it expires, we don't renew it, we just get another one when we need it again. We usually get three trips off one pass. For example, we need new passes again, our old ones just expired today. We will get them for our Christmas 2002 trip. Then we will use them in July 2003 and Nov 2003. Then we will buy another new one in summer 2004 and do it again. Renewals are bit cheaper than new ones, but not worth the cost to us.
Discounts vary by resort type - deluxe, moderates, etc. Also by time of year.
You can also purchase a Disney Club card yearly to get discounts on lodging, tickets, meals and activities. They change from time to time, and do not include every dining facility and resort.