Comment 0 for bug 1446552

When an installed package adds a dependency that is not yet installed on the system, this sometimes causes the package to not be installed, depending on the origin containing the original candidate version.

I believe that the problem is in /usr/bin/unattended-upgrade, line 102. Here a check is performed to prevent downgrades. However, as a side effect it also prevents adjusting the candidate version for packages that have not yet been installed (because pkg.is_upgradable is False for packages that have not been installed).

This makes updating private packages using unattended-upgrades troublesome, especially when new dependencies have been added. Currently it requires repackaging the dependencies with a slightly higher version number than what is in the main repository, and than hosting them on the private repository, which is time consuming and error-prone. With the included patch, it is sufficient to just host the same version on the private repository.