Upgrading distro invalid packages

[Arwen]

Just trying to upgrade from 18.04 to 20.04.
Description: Ubuntu 18.04.5 LTS
Release: 18.04

Ran sudo do-release-upgrade
Get this message
Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

This was likely caused by:
* Unofficial software packages not provided by Ubuntu
Please use the tool 'ppa-purge' from the ppa-purge
package to remove software from a Launchpad PPA and
try the upgrade again.

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'.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.44
ProcVersionSignature: Ubuntu 4.15.0-142.146-generic 4.15.18
Uname: Linux 4.15.0-142-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.23
Architecture: amd64
CrashDB: ubuntu
Date: Wed May 5 18:07:15 2021
InstallationDate: Installed on 2021-05-04 (0 days ago)
InstallationMedia: Ubuntu-Server 18.04.4 LTS "Bionic Beaver" - Release amd64 (20200203.1)
PackageArchitecture: all
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2021-05-05 (0 days ago)
VarLogDistupgradeLspcitxt:
 00:00.0 Host bridge [0600]: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX Host bridge (AGP disabled) [8086:7192] (rev 03)
 00:07.0 ISA bridge [0601]: Intel Corporation 82371AB/EB/MB PIIX4 ISA [8086:7110] (rev 01)
 00:07.1 IDE interface [0101]: Intel Corporation 82371AB/EB/MB PIIX4 IDE [8086:7111] (rev 01)
 00:07.3 Bridge [0680]: Intel Corporation 82371AB/EB/MB PIIX4 ACPI [8086:7113] (rev 02)
 00:08.0 VGA compatible controller [0300]: Microsoft Corporation Hyper-V virtual VGA [1414:5353]

[Brian Murray (brian-murray)]

Thanks for taking the time to report this upgrade failure. There is currently a new version of the release upgrader availalbe in -proposed which may resolve the error you've encountered. Please run the following command to test the new version of the upgrader:

  do-release-upgrade -p

Please lets us know the results in this bug report. Thanks again and good luck!

[Launchpad Janitor (janitor)]

[Expired for ubuntu-release-upgrader (Ubuntu) because there has been no activity for 60 days.]