If the multiple contracts are a Master - Add on combination, then yes. At 7 months you may freely combine points with no problems or extra steps. You have a Master-Add on combination if all of the contracts have one membership number. The Master contract will have a number like XXXXXX and the add ons will have a number like XXXXXX.001, XXXXXX.002, etc.
If you have more than one membership number for the contracts, then it gets a little more complicated. You have to reserve nights from each contract and have MS link them together. You cannot use points from more than one contract for the same night without doing a transfer.
For example, if a single night costs 12 points, you can't use 7 points from one contract and 5 from another to make the reservation. You have to transfer points between contracts so that all 12 points are in a single contract. Since you are only allowed one transfer per use year per contract, that would use up your allotment of transfers for both contracts. If the contracts have different use years, then you can only "combine" the points at the 7 month window.
In no case, can you combine points from contracts with different use years to make a reservation at a
DVC resort at the 11 month window.