If you don't use your deeded week, you would use your SOs to book another week, which can't be done until 8 months out. If you are flexible as to when you can travel and can travel during non-peak times, your chances of securing another week are pretty good, if you can reserve at midnight 8 months out (as of now), although it may or may not be a VGV unit. If its a VGV unit with a pool you're looking for, your odds are very low, since most owners use their units or rent them out.