It's not a big deal, because you can download the episodes from another section of the site - but that doesn't let you listen to them in sequence, which I was rather enjoying. I'm caught up to about 2006, and I'm really enjoying the way Melvyn Bragg structures a season.
I think these are what we call "first world problems".
Ah OK I misunderstood what you were getting at, there. Well.. I don't have that much to do with the iPlayer internals, I'm in a different department. You could raise it as a complaint - those usually get looked at by the right people.