The F-35B isn't going to be cancelled, there is too many countries depending on it and its capabilities make it irreplaceable (in the next 20 years).
My bold
US Marine Corp at 340 ish
RAF/RN at <138
Marina Militaire at 22
Can't see any other customers and we were the ones wanting to pull out.
Smoke and mirrors, I suspect MoD have gone back to the expensive short legged version to dig the MC out of a hole, maybe under threat of losing that national design sovereignty stuff of a couple of years ago?