Welp, in a last ditch effort to try and reallocate my banked points to an earlier reservation.. I wound up losing a night. I modified my reservation to be one day shorter and tried to rebook it as a separate reservation. I searched in another window immediately after completing the modification and the room was available! Clicked continue to book and get 'we're sorry the room is no longer available, please try your search again' and the room is now gone. I guess this could be evidence that they're grabbing waitlist room inventory immediately instead of a job that runs at a certain time of day? I don't know, but now I'm homeless for a night with flights already booked and not enough points to book another room.