You probably have /etc/apt/apt.conf.d/20auto-upgrades or another file later in the search order that overrides the setting, 20auto-upgrades is what unattended-upgrades configures.
** Changed in: apt (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to apt in Ubuntu. https://bugs.launchpad.net/bugs/2055711 Title: Cannot set APT::Periodic::Update-Package-Lists Status in apt package in Ubuntu: Invalid Bug description: On Ubuntu 22.04.4 running apt 2.4.11 (amd64), I cannot set APT::Periodic::Update-Package-Lists. No matter which value I enter, it is always interpreted as '1'. Steps to reproduce: 1. Open /etc/apt/apt.conf.d/10periodic 2. Enter APT::Periodic::Update-Package-Lists "2" (or any other number, or "3h" or "always") 3. Save and exit 4. Run sudo apt-config shell UpdateInterval APT::Periodic::Update-Package-Lists 5. The console prints UpdateInterval='1' Changing other config options, like APT::Periodic::Download- Upgradable-Packages, works. Changing the order of the lines in 10periodic does not affect the result. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/2055711/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp