I was called away overseas on business for around 3 weeks just after Christmas and during that time my PC crashed meaning no radio downloads took place. On return I've refreshed and tried to catch up on the missing downloads by looking up the past schedules and doing my usual command line:
get_iplayer --type=radio -get "prog name 1","prog name 2",  etc
but the downloads during that period seem to be missing - the only way to download is by getting the PID of each one. When doing that, I get a "programme not in the cache" type message.

When I joined the forum I seem to recall reading somewhere about how to keep the cache up to date but my searches to find the reference have proved fruitless. Can someone please educate me how to make sure I don't get these "gaps" in the cache again and, more importantly, how I can put it right after the fact!

See Config section of Options page in wiki

Errr? I looked at that section and all I could find was the refresh command --refresh which I use, as implied above. Could you be a bit more explicit please? How often do I need to do a refresh to ensure I have a complete 28 day cache without gaps? Unless there's something different I need to do?

HV

Oops - check the wiki again. The option you seek has been un-deprecated, so has now been moved from Deprecated section back to Config section of wiki page.