Насколько я знаю, вы должны иметь возможность использовать стандартные опции с apt-get dist-upgrade, чтобы имитировать выполнение этой команды без фактического выполнения обновления.
-s, --simulate, --just-print, --dry-run, --recon, --no-act No action; perform a simulation of events that would occur but do not actually change the system. Configuration Item: APT::Get::Simulate. Simulate prints out a series of lines each one representing a dpkg operation, Configure (Conf), Remove (Remv), Unpack (Inst). Square brackets indicate broken packages with and empty set of square brackets meaning breaks that are of no consequence (rare). -u, --show-upgraded Show upgraded packages; Print out a list of all packages that are to be upgraded. Configuration Item: APT::Get::Show-Upgraded.