I think, it means that you can make your ADR's (up to 10) at the 90 day point, instead of calling back day after day to make your dining reservations.
It just lets you make more than one ADR at the 90 day mark. IF I were you, based on what I've been reading, I'd call immediately at the 90 day mark, to make your ressie's.
DO NOT wait until 10 days before arrival!!!!!