Turns out to be a version issue, the right one with the fix is 0.53.0+git202204060855+pkg151~ubuntu22.04.1. Anything older than that will continue to fail submitting tarballs to C3.
Turns out to be a version issue, the right one with the fix is 0.53.0+ git202204060855 +pkg151~ ubuntu22. 04.1. Anything older than that will continue to fail submitting tarballs to C3.