Using blogdown-jekyll with _collections directory

[wamber-aww]

I've tried using this with _posts and it works great - the Rmd files autoregenerates on its own the also makes a figure directory at the base directory. However, if I make other directories that are not called '_posts' and change the .Rprofile blogdown.subdir = '_collections', I can't autoregenerate the Rmd files anymore. I was wondering if you have any insights into this. I'm probably just missing something very obvious but couldn't figure it out.
Thank you!