I admit that I haven't tested comprehensively, but this does appear to be correct, at least the 10 nights part.
In theory, you could find a stretch you want with suite availability, book ten nights around it on points, shorten the reservation to what you want, then apply the TSU.
But, this is truly getting ridiculous. And the prices here are also increasing rapidly.
Of course, many of us really like this place, so it's hard to argue with the rules of supply and demand.