That is in fact part of the problem here, “repeat airings” is not actually explained properly anywhere.
New obviously only records if the guide data indicates it’s ‘new’, fair enough - but that’s not what everyone wants/needs, so the only other option is “New and repeat airings”. So you select that, but at least in my case it’s then repeatedly re-recording things that are already in the broader library, as well as things it’s already recorded and doing so at a lower quality. I.E. it already knows it has a 720p version, why is it snagging an ‘SD’ version at all?
Even searching this forum there’s a lot of folks who say that if you have ‘repeat airings’ enabled it won’t re-record, and a fair number of folks reporting findings similar to mine that that doesn’t seem to be the case - case in point: Does "New and Repeat Airings" record duplicate episodes or simply allow "previous" episodes as well?
So this boils down to:
- Have I miss-understood what the ‘New and repeat airings’ does? Empirically: sorta, it does what it says on the tin, just not what I’m expecting (I.E. don’t re-record things it already has)
- Are the folks claiming that it doesn’t re-record somehow doing something different and/or do I just have it set wrong? From everything I can find no, but the Plex docs don’t seem to cover this super well.
- If Plex doesn’t actually support this (which I believe is what @OttoKerner is saying here) then is there a way to get something like what’s in Jellyfin and Emby added to plex for:

to make it super obvious what’s going on for folks?