GUI and CLI background migrations count doesn't match after upgrade

I have just finished 14.9.5-ee.0 to 14.10.5-ee.0 upgrade and this URL reporting background migration:
https://our.instance/admin/background_migrations
shows that there are still some migrations whereas the following command:

gitlab-rails runner -e production 'puts Gitlab::BackgroundMigration.remaining'

display 0 (zero).
Can anyone explain why they don’t match?

I have a feeling the CLI one using gitlab-rails hasn’t worked for a while now. Since the feature appeared in the web interface, I found it stopped working.

That is not very good news as (at least for the upgrade process) I would like to use CLI for all the steps and skip the GUI.