An unresolvable problem occurred while calculating the upgrade

[Christian Kujau]

$ grep ^Pr /etc/update-manager/release-upgrades
Prompt=normal

$ sudo do-release-upgrade
[...]
Checking package manager
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done

Calculating the changes

Calculating the changes

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 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal. If
you want to investigate this yourself the log files in
'/var/log/dist-upgrade' will contain details about the upgrade.
Specifically, look at 'main.log' and 'apt.log'.

Restoring original system state

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: ubuntu-release-upgrader-core 1:22.04.19
ProcVersionSignature: Ubuntu 6.5.0-28.29~22.04.1-generic 6.5.13
Uname: Linux 6.5.0-28-generic x86_64
ApportVersion: 2.20.11-0ubuntu82.5
Architecture: amd64
CasperMD5CheckResult: unknown
CrashDB: ubuntu
Date: Mon May 13 17:51:20 2024
PackageArchitecture: all
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to jammy on 2024-05-13 (0 days ago)
mtime.conffile..etc.update-manager.release-upgrades: 2024-05-13T16:47:29.516789