You can book up to about 2-3 weeks in advance of your trip.
The dining reservations number is 0033 160304050.
JillRobinson is right, they will only ask for the surname of the party you want to book under, and thats the name you give at your chosen restaurant when you arrive for your meal. They also gave me a reference number when I booked, but I was never asked for it at the restaurant, just my surname.
Elaine