In the repository rename from unstable stable the asgen_push (I think that's the script anyway) logic wasn't updated, so appstream data is still being put into /dev/unstable etc.
this results in broken/outdated appstream data in the new repos /unstable etc. and sad Nate and Aleix
fix the publishing
ALSO stop publishing the old repos and instead turn them into symlinks pointing to the new repos! the double publishing has a huge impact on build performance