Remove Unavailable Episodes

Looking at some BBC podcasts I started getting 404 errors. I realised that some of the old podcasts are no longer available but still visible in the list of episodes within AntennaPod.

Example PopMaster

In my copy I see Podcasts going back months but online there only seems to have around 1 month available. It would be good to be able to remove automatically old episodes that are no longer available when a refresh/update is done. Obviously if the episodes have already been downloaded then the episode should remain until it is deleted from local storage.

Looking at the RSS I see that there is the following tag

<ppg:seriesDetails frequency=“daily” daysLive=“30”/>

Which I think gives the clue to what is happening