Ratpack:
When I called this a.m. I asked specifically re rates for late May/early June. Check out this link to Deb's website on previous AP offers and dates they came out/periods of time they covered.
keriannhoward:
As long as there are rooms available under the code/discount rates you should be able to convert your existing reservation to the new rate. I would definitely reserve the resort/dates you want now (at rack rate or AAA if you are a member), then check back frequently here or at mousesavers.com for deals..............