Keep most recent X unwatched episodes of a show

In Plex, I am able to “sync” (the Plex way of downloading to iPad) a show, such that:

  1. when new episodes appear, they are downloaded.
  2. I can select it to keep in sync only the X most recent episodes or X most recent unwatched ones. This means that every time my iPad connects, it will add new episodes if needed, AND delete downloaded ones that have already been watched.

The above is configured directly when I initially pick “sync” for any show (presumably here it would happen if I select download for a tv series).

This makes life very “easy”, where I can just pick a bunch of shows I watch, mark them like that, and my iPad never runs out of space but always has ready episodes for me to watch of any show I am following.