do-release-upgrade could not calculate the upgrade

[Edwin Wisse]

do-release-upgrade terminates without upgrading. Message on terminal:

   Could not calculate the upgrade

   An unresolvable problem occurred while calculating the upgrade.

   If none of this applies, then please report this bug using the command...(etc)

It gives no indication what the problem might be or how i can resolve it.

apt.log contains a lot of lines like:

  Setting alsa-base:amd64 NOT as auto-installed (direct Depends of ubuntu-desktop:amd64 which is in APT::Never-MarkAuto-Sections)
  Setting alsa-utils:amd64 NOT as auto-installed (direct Depends of ubuntu-desktop:amd64 which is in APT::Never-MarkAuto-Sections)
  Setting anacron:amd64 NOT as auto-installed (direct Depends of ubuntu-desktop:amd64 which is in APT::Never-MarkAuto-Sections)
  etc.

But it is not clear how it can be resolved.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.38
ProcVersionSignature: Ubuntu 4.15.0-118.119-generic 4.15.18
Uname: Linux 4.15.0-118-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.17
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Sat Oct 3 13:03:09 2020
InstallationDate: Installed on 2018-12-24 (648 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2020-10-03 (0 days ago)

[Brian Murray (brian-murray)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1898152, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.