CI not working after upgrading to v14.6.0

A few days ago we updated out self-managed instance to v14.6.0.

The update was seemingly successful, but the CI is completely dead.
No pipelines are triggered at all, on any commit.

Something that I noticed is that the new update caused the creation of a few background migrations:

  • BackfillIntegrationsTypeNew: integrations
  • BackfillUserNamespace: namespaces

These are stuck to 0% for about a week now. I cannot see any sign of progress.

Any ideas on how to diagnose the CI issue?
Can it be related to the background migrations?
Can I do something about these stuck migrations?