I wanted to upgrade a production system (through staging, first) to 20.04. Backups and recovery options were in place. All went smoothly as expected. I did do-release-upgrade -d, because I didn't want to wait until the first point release (20.04.1).
However, reviewing all the configuration changes (a combination of looking at diffs from etckeeper and matching with debsums -ce), I noticed /etc/apt/apt.conf.d/50unattended-upgrades now has this line:
Unattended-Upgrade::DevRelease "auto";
This was previously set to:
Unattended-Upgrade::DevRelease "false";
And so I was wondering if this in line with my desired configuration. I'd like to be able to use unattended-upgrades as before, but I definitely don't want anything other than LTS releases.
I looked at the manual pages for apt.conf, apt_preferences, apt-config and unattended-upgrade, but could not find a description of that configuration option. This community help page also didn't list the option. This question here on AskUbuntu was the only one referencing this particular option, but doesn't answer my question either.
Q: So what does Unattended-Upgrade::DevRelease do when set to "auto" and where can I find more information about the settings and their respective effect?