Right now how the program works for the best rate program you need to book more than 120 days out (about 4 months) and put down a non-refundable deposit of one nights stay immediatly. No more 14 day grace period. If you have to make any changes that result in your balance being less than it previously was there will be a $50 change fee implemented.
In order to use this new best rate program you will have to have an activated annual pass or voucher in hand. You will need to enter the number from the back of either card to access the site and reserve your room.
They will still have call in rates like they used to. I.E you book a room and IF an AP rate is released you can apply it towards your existing reservation. I assume that the call in rates will be much more limited than the best rate program.
Also know that the rates are not guaranteed. You may also have to be flexible with your dates, and resorts as there may not be availibility with the discount for your particular duration of stay or resort choice.
HTH some