I can't speak to the cancellation line, since I saw Waves at the National in London, but I can speak to it's quality; which is amazing.
I will add the caveat, it is not the easiest piece to get through (but frankly, neither is the novel) but for the imagery alone in act 2 (the first 15 minutes are really quite ingenious). (I was also remarkably tired when I saw it [this was the tail end of a 26 production 2 week Edinburgh/London smorgasbord] so maybe that made my job a bit harder).
The one show everyone on Broadway is waiting to see: Twyla Tharp presents: Big Bottom - The Spinal Tap Jukebox musical!