You can call at the 180 day from check in date and make reservations for that date and the next 10 days of your reservation so you don't have to call at the 180 day point for each reservation if you are trying for something that may be a little hard to get. This is available to people staying at Disney resorts. There are a few restaurants that will only take the reservation at exactly the 180 mark however and you may have to call back for those. I had to do this for Wolfgang Puck Cafe.