Comment 6 for bug 1385410

We figured out a way to be able to do it before reboot, and this is something that is needed for systemd and helps usability of traditional apt systems in addition to system-image systems.

The idea is there are no extra steps for the user to go through, but yes the idea is there would be a progress meter after the user presses 'Install and reboot' (though even that isn't strictly required but since it could take awhile, it seems to make sense).