Podcast automatic downloads stop after 15 days

If I haven't listened to a particular podcast in 15 days, the automatic downloads stop, and this is very annoying. I have 100 GB of free space, it only keeps the 5 most recent episodes of any podcast anyway, so this storage-space saving "feature" is not needed. I can't find any way to turn it off, is there one?

In lieu of that, does anyone use Amazon Music (with Prime but without an unlimited subscription) or Audible (with subscription) to listen to podcasts instead, and does this solve the problem?

(I'm using this on my iPhone)