Seems to be a problem with koji: a bunch of build tasks are not closing. Some of them are koschei builds but seems like they are all stuck during or after building.
For example the python-xarray-0.12.3-2.fc31 has been running over 30 hours!
This queue seems to be preventing any new builds from happening.
This was due to the rabbitmq cluster having issues. Should be working again now...
Metadata Update from @kevin: - Issue close_status updated to: Fixed - Issue status updated to: Closed (was: Open)