There are a few posts about those shows in the thread I linked above, starting here. Apparently it’s due to the EPG providers not flagging these as new (with the assumption that that’s because PBS isn’t submitting them as new).
I’ve been manually setting up my recordings for both shows due to this situation. In the off-season, I create a recording schedule to record all (new and repeat) episodes and configure it to delete watched episodes after a day. In this way, any repeats I’ve already seen and deleted, but which get recorded again, will be automatically deleted, leaving only new, unwatched episodes.
