This turns out to be the result of the change from using commit hashes to branch names in modulemd.
I've got a fix, but I still need to verify it before submitting a PR.
Commit 411da3de fixes this issue
@ralph changed the status to Closed
Closed
This issue has been migrated to Fedora Forge: https://forge.fedoraproject.org/koji/mbs/issues/203
Please continue any further discussion there.