Comment 17 for bug 2049785

I got a Bionic ISO and run it in a virtual machine.

Enabled proposed and now upgrading update-manager forces the installation of a newer ubuntu-advantage-tools:

--->
$ sudo apt install update-manager --verbose-versions
Reading package lists...
Building dependency tree...
Reading state information...
The following additional packages will be installed:
   python3-update-manager (1:18.04.11.23)
   ubuntu-advantage-tools (31.1~18.04)
   ubuntu-pro-client (31.1~18.04)
   ubuntu-pro-client-l10n (31.1~18.04)
   update-manager-core (1:18.04.11.23)
The following NEW packages will be installed:
   ubuntu-pro-client (31.1~18.04)
   ubuntu-pro-client-l10n (31.1~18.04)
The following packages will be upgraded:
   python3-update-manager (1:18.04.11.13 => 1:18.04.11.23)
   ubuntu-advantage-tools (27.2.2~18.04.1 => 31.1~18.04)
   update-manager (1:18.04.11.13 => 1:18.04.11.23)
   update-manager-core (1:18.04.11.13 => 1:18.04.11.23)
4 upgraded, 2 newly installed, 0 to remove and 376 not upgraded.
Need to get 820 kB of archives.
After this operation, 1,570 kB disk space will be freed.
Do you want to continue? [Y/n]
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I confirm then that launching and finishing update-manager without internet connection produces no error any more.