I would imagine a big-ass update like this (removing half of BLOCKLAND, and adding something huge) would make it a new version completely.
it's just the name, the updater was made for a reason, to update things, and badspot is updating the shaders and we will probably have to download a r1521 or something similar.
it's silly for a new version, sure i don't mind but it's absolutely silly and the 'verison 21' has not been announced, only shaders.