(Sorry I’m not really trying to overtake the thread with a guaranteed week discussion but the OP did express some interest in it and they are considering buying at Riviera. I’m just trying to point out what might be a useful consideration, whether the OP actually does so or not, I thought it was useful to make the case.)
In actuality, for the first time, we’re considering adding Riviera points. We stayed there and absolutely loved it. But, since we already have experience with fixed weeks, for us, it’s a no-brainer to add that as a hedge against any 11-month difficultly booking that might result from the resale restrictions.