+1 on subscribe from the beginning! I started listening to the British History podcast this year, and so far on PocketCasts I haven't found any decent way of managing listening to 5 year old episodes other than downloading them ten or so at a time. (So there's always the next one to listen to downloaded to my phone, rather than remembering episode numbers.)
> I started listening to the British History podcast this year
OT, but if you're interested in British History you might be interested in This Sceptred Isle. Most of it isn't available on iPlayer, but it should be in the usual places.