If you know somebody who is a member then getting in touch with them ASAP is a good idea, just to make sure it is all planned out and ready. If you don't know anybody with a club membership, then your options are to a) get to know a member b) get on the waiting list which is a good 5-10 year wait (just like AwesomeMan33 stated).
It's not impossible, but it is somewhat tricky getting a reservation there - I wish you lots of luck though!
"I, not events, have the power to make me happy or unhappy today. I can choose which it shall be. Yesterday is dead, tomorrow hasn't arrived yet. I have just one day, today, and I'm going to be happy in it. "Groucho Marx
Members can make reservations 3 months out for their own groups and two months out for parties they do not accompany. Technically. The Club opens up an entire new month at the beginning of each month. Currently they are booking through October for member dining parties, and September for dining parties that do not have a member present.
I would be a guest of a member, but I dont want to ask to early?
Maybe you should trust that the member knows what he or she is doing and will book you in plenty of time?
Good morning, son
In twenty years from now
Maybe we'll both sit down and have a few beers
And I can tell you 'bout today
And how I picked you up and everything changed
It was pain
Sunny days and rain
I knew you'd feel the same things...
Members can make reservations 3 months out for their own groups and two months out for parties they do not accompany.
Correct for Gold Members.
However...if your sponsoring Member is only a Silver Member (a level they do not sell new memberships of anymore, but there are still existing Silvers out there)...they can only make advance reservations 3 months in advance for Sunday thru Thursday only. For Fridays and Saturdays...Silvers can only make reservations 30 days in advance (if available, of course).
Also regarding the December Holiday Season (if that's the "holiday" you are referring to):
Gold (Corporate, Corporate Associates, Limited-Corporate, Individual): Reservations open in August for Member-accompanied parties. Reservations open in October for guests of Gold Members where the Member will not be present.
Silvers: Reservations open in September for Member-accompanied parties. Reservations open in November for guests of Silver Members where the Member will not be present.
So for you as a guest of a Member if the Member is not going to come along with you:
If they are a Gold...hit them up the first of October.
If they are a Silver...hit them up the first of November.
If you aren't sure what level your sponsor has...I would assume its Gold (they are by far the most common in numbers) and ask them to check the first of October for you.
December can be a very difficult month to get reservations in. Lots of large company parties and even private parties where the entire Club is booked by one member...happen in December. Good Luck!