Before af24915 the message was:
* Updating binary package linux-x86_64/gdal/2.4.1.tar.gz...
curl: no URL specified!
curl: try 'curl --help' or 'curl --manual' for more information
* Binary package is still up to date
the script was broken, and the message could not be trusted, because it didn't actually check the package URL.
After af24915 it is:
* Updating binary package linux-x86_64/gdal/2.4.1.tar.gz...
* Binary not available yet for linux-x86_64/gdal/2.4.1.tar.gz
Now it actually checks the URL, but then says it's not available. I'd assume curl should succeed with HTTP status 304 Not Modified, but it appears to work differently.