Comment 3 for bug 1773859

Apologies for the double-comment.

Following the guide from here...
https://askubuntu.com/questions/838491/systemd-shim-error-after-upgrading-from-16-04-to-16-10/838673#838673

I was able to continue upgrading with these commands:

[let upgrader bail out and run dpkg configure]
sudo mv /usr/share/dbus-1/system-services/org.freedesktop.systemd1.service /usr/share/dbus-1/system-services/org.freedesktop.systemd1.service.bak
sudo apt-get install -f
sudo apt dist-upgrade
sudo apt autoremove

Then, to optionally finish cleaning up, check what packages are no longer supported using the command from...
https://askubuntu.com/questions/691051/how-to-get-the-list-of-the-unsupported-packages-mentioned-during-the-os-upgrade

awk -F\' '/demoted/ {gsub(/ /,"\n",$2); print $2}' /var/log/dist-upgrade/main.log

The system in question appears to work fine now, just the usual cleanup of changes for any major OS upgrade.