Since the fix for LP: #1577215 u-u does not change to origin list based on debconf answers, but it still changes if u-u is enabled by setting APT::Periodic::Unattended-Upgrade to 0 or 1 in apt.conf.d/ .
The debconf template name is: unattended-upgrades/enable_auto_updates .
Probably the installer does not set it properly.
Since the fix for LP: #1577215 u-u does not change to origin list based on debconf answers, but it still changes if u-u is enabled by setting APT::Periodic: :Unattended- Upgrade to 0 or 1 in apt.conf.d/ .
The debconf template name is: unattended- upgrades/ enable_ auto_updates .
Probably the installer does not set it properly.