Advantage to 2 contracts- you can sell one and keep one if you need money for an emergency or something. You can make 11 month reservations at 2 resorts at the same time.
The problem is if you want to make a continous reservation at one resort using all the points. You then have to wait for the 7 month window to use all your points at 1 resort. If you have points at 2 resorts, and different months for renewal, that's a whole other set of problems.