DVC villas are all usually booked on points for the marathon early. If you don't book it at seven months out, you could still waitlist and see if you can get anything. But multiple nights for a stay during that time are going to be extremely difficult to book if you haven't waitlisted already.
Several years ago, we tried to add one more night to the start of our marathon trip via waitlist and couldn't get it. I think we waited until about four months out. We wound up booking a single night for cash at SSR. It was the night before the start of the Expo.