You must book a rack rate room/tickets package for a period usually in late August/early September. You can book the promotion only while it is available for booking. It was released for booking this year the first week of April (a couple of days were reserved for Disney Visa customers and then the booking was opened to the general public) and you had to book by June 22, so if your friends were thinking of going this year, they won't be able to book free dining.