Competitiveness of an RY between M3-M4 specifically

There is a lot of info on the subreddit about post-graduation RYs. Does anyone know how competitive it would be to finesse a research year between M3 and M4? there seem to be a lot of programs based on the spreadsheet, but i wouldn't know how many to apply to (4-5 vs 18-20, but i'm hoping that's not the case!). Any info/input you might have would be super helpful, thanks!