Thanks Bastian - I'll re-upload the package with an initial Debian revision (1) soon.
(I'll also try to find a way to build it as a multi-arch amd64 arm64 package in a way that does not classify as FTBFSIASW - probably using some useful discussion on -mentors re: mergechanges)
Please note that you have to keep the Debian revision at -1 until this is sponsored.
Uploading an existing package version to mentors will just overwrite the old package.