DVR Error when selecting library to record in

I have a folder “TV Recordings” that is in 2 libraries, “TV Shows - All” & “TV - Recordings Only”

If initially I select the latter to record in I get error “There was a problem saving your changes. Please try again.”

However, if I select the former initially I can then successfully change it to the latter after it’s been set-up

This is on 1.13.2.5102 but has been doing it for many versions prior

I don’t want it in the former as that won’t record all episodes that may already exist there unless I select to “Replace lower res items” but that will delete existing items whereas I want to keep both versions & maybe tidy later.

Any thoughts?