Actually, for that particular thing, I have two "catch-up" files posted on jumbofiles.com (with a big box link on my episodes page headed "NEW TO 19 NOCTURNE?"). They're zip files of 13 episodes each, and they have been getting quite a lot of downloads.
Plus I have all the back episodes on the website individually for download.
I don't have the Libsyn bandwidth (and don't want to pay for it) to include TOO much in a month.
My big problem is getting the podcatchers to recognize the new feed and let go of the old one.