Usually within a few hours of buying add-on points, they are available for use. I'm not sure how long it takes when you are a new member, as they also have to set up an account for you but I believe it is still within a day or so. My first contract was via resale, which take longer to load after they close. With direct contracts you are able to make a reservation prior to closing (obviously). You can make the purchase contingent on a specific reservation you want when you talk to your guide (salesperson) and they can see if they can pull some strings to get you in.