The suggestion from Igor finally worked although not right away in my
case :)
These two:
sudo apt install --only-upgrade ubuntu-release-upgrader-core
sudo apt dist-upgrade --allow-downgrades
Managed, probably, to get the system past the error of this ticket but
afterwards I wasn't able to login
I can confirm the same issue. After upgrading to 24.04.1 from 22.04.5
Discover shows about 1400 packages need to be updated again. When trying
to update the all, I get this error:
WARNING: You are trying to remove the following essential packages:
libapt-pkg6.0 (due to apt) libgnutls30 (due to apt