When the first day of your resort reservation is 90 days in the future, you can make all of your ADRs for the first day and up to 10 days of your trip.
For example:
Today: 10/15/05
Resort Reservation Begins:1/15/06
Resort Reservation Ends: 1/22/06
You can make reservations for 1/15/06 as well as reservations for 1/16/06 thru 1/22/06 when you call on 10/15/05. Previously you would have to call to make ADRs for 1/15/06 on 10/15/06 and call again on 10/16/06 to make ADRs for 1/16/06, etc. Now it can be done in one phone call.
Note: I just made up the dates and didn't try to calculate which day is exactly 90 days from 10/15/05.