I think it's been about 6 months or more for me and I am also very satisfied with it. I left NewPipe because I'd often have to wait days to weeks for simple fixes to get implemented. PipePipe is patched very often.

I think part of the reason why NewPipe is so slow is that they are in the middle of a rewrite/redesign. All the focus is there and the current app is in the maintainance mode.