It seems reasonable that setting TZ=UTC0 for date --iso-8601 could help (as that's where a time zone is relevant, the +%s conversion it is not relevant for).
But then this causes unwanted behaviour for people far off UTC, I guess, so it's not a solution - It's entirely unclear to me whether a solution exists given that we allow arbitrary intervals in settings. Always-on machines (or well, always connected machines) should be configured with the interval set to 0 (disabling timestamp checks), and the timer should be configured to run at the appropriate times. To resolve issues with skipped runs elsewhere, we really need to resolve the issue that systemd can't reschedule failed timer services, and then remove the options inside apt.conf, as having dynamic timers in systemd and then a fixed check inside the script does not really work (hence why we annoyingly run it twice a day to give it a chance to fixup time skew). ** Changed in: apt (Ubuntu) Status: Confirmed => Won't Fix ** Changed in: apt (Ubuntu) Status: Won't Fix => Triaged -- 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/1824088 Title: unattended upgrade ran one day after schedule Status in apt package in Ubuntu: Triaged Bug description: I have noticed a strange behaviour in unattended upgrades. The host in question is scheduled to run upgrades on Mondays every second week. However, this week it ran upgrades on Tuesday instead (2019-04-09). This is the first time I’ve noticed this behaviour. I checked the logs in /var/log/apt/history.log* and I saw that worked as intended up until this week. Upgrades ran as expected on 2019-03-11 and 2019-03-25, which where both Mondays. The schedule was set with the line 'APT::Periodic::Unattended-Upgrade "14";' in the file /etc/apt/apt.conf.d/20auto-upgrades. Could it be daylight savings time that has caused skewing of the schedule? The server is located in Sweden and on 2019-03-31 we switched from CET to CEST. If the time diff is calculated with hours instead of calendar days passed, perhaps the missing hour on 2019-03-31 caused the scheduler to believe that on Monday 2019-03-08, two weeks (336 hours) had not yet passed. ADDITIONAL INFO Description: Ubuntu 16.04.6 LTS Release: 16.04 apt: Installed: 1.2.29ubuntu0.1 Candidate: 1.2.31 Version table: 1.2.31 500 500 http://se.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages *** 1.2.29ubuntu0.1 500 500 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages 100 /var/lib/dpkg/status 1.2.10ubuntu1 500 500 http://se.archive.ubuntu.com/ubuntu xenial/main amd64 Packages unattended-upgrades: Installed: 0.90ubuntu0.10 Candidate: 0.90ubuntu0.10 Version table: *** 0.90ubuntu0.10 500 500 http://se.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages 500 http://se.archive.ubuntu.com/ubuntu xenial-updates/main i386 Packages 500 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages 500 http://security.ubuntu.com/ubuntu xenial-security/main i386 Packages 100 /var/lib/dpkg/status 0.90 500 500 http://se.archive.ubuntu.com/ubuntu xenial/main amd64 Packages 500 http://se.archive.ubuntu.com/ubuntu xenial/main i386 Packages ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: apt 1.2.29ubuntu0.1 ProcVersionSignature: Ubuntu 4.4.0-142.168-generic 4.4.167 Uname: Linux 4.4.0-142-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.18 Architecture: amd64 Date: Wed Apr 10 09:06:49 2019 InstallationDate: Installed on 2017-12-28 (467 days ago) InstallationMedia: Ubuntu-Server 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801) SourcePackage: apt UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1824088/+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