I have not figured out what to make of this yet, but as I started reviewing the radio station data, I realized that the updates have not been happening for many months. The reason is curious.
As a sanity check to prevent problems in the event of a partial download, I do a test to make sure the file that I’ve downloaded from the FCC is approximately the correct size. If not, the update fails and nothing is updated.
For the FM stations, my script was testing to make sure that the download was at least 14 MB of data, but as of today the complete file appears to only be 12.4 MB. I don’t have a clue how 15% of the FM radio station licenses could have vanished.
It is possible there has been a big Purge of low power FM licenses and/or translators. This is also possible that the data for each radio station has shrunk for some reason. It’s getting late and I don’t yet know the answer, but if anybody notices strange things about the FM stations, that is why