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  • Time not updated when phone was off / in airplane mode

Hello,
Time and timezone are both set to "automatic". I often use my phone in airplane mode and often switch it off at night and switch it back on the next day (or even the day after), while being in airplane mode and WIFI off.

When I start the phone then, the time is several hours behind actual time. When I enable WIFI, the time is not updated. I have to open settings, switch "automatic" off and back on, to get it updated.
If I don't do keep in mind to manually "sync" that way, stuff I do gets the wrong timestamp (eg. files).

Time sync should be "automatic" for security reasons. I see in the log of RethinkDNS that GOS connects to time.grapheneos.org when the phone was started. Why doesn't it remember, that it did not succeed synching at startup, and make up for it when I connect to WIFI?
And why is the time so terribly out of sync (by several hours) if I switch the phone off at night? I mean the phone had battery power (even if switched off).

Any hints on what I am doing wrong? Please advise.
Thank you and best regards

    TRInvictus According to the project account, automatic time zone uses the cellular network's time zone: https://discuss.grapheneos.org/d/10843/4. If you're in airplane mode, then I'm not sure how the phone can determine where it is.

    Also, phones and computers only display time in different time zones for people. If the time is right but the time zone isn't, then that's not an issue security-wise, just confusing. I might be wrong about this, but if you disable airplane mode, then even if you don't have a SIM for the networks your phone is connecting to, the phone should still get the correct time zone from the cellular network. That has been my experience when traveling abroad, at least.

    TRInvictus And why is the time so terribly out of sync (by several hours) if I switch the phone off at night? I mean the phone had battery power (even if switched off).

    I've personally never tried that since I use my phone as an alarm. I don't think it should be a problem as long as your phone can get the correct time shortly after starting up.

      other8026 Ok thank you. By saying "time is terribly out of sync", that has to be the time zone then, as there is no WIFI (off = no time sync) and no connection to cell network (airplane mode on = no time zone sync). I have to check, if the minutes are still correct, then it's definitely the "human readable" time zone. I'll keep an eye on that...

      11 days later

      Last night, time of day was ok, I switched my phone off, with airplane mode on, wifi off. Both time and timezone still "automatic" in settings.

      Today, switched my phone back on, still airplane mode on, wifi off. Time of day was behind of 1 hour and 50 minutes.

      Connected to wifi, airplane mode still on, both system and apps checked for updates (and reported everything up to date), so wifi was connected and working for sure. Time was not updated automatically. I had to go to settings, switch auto off and back on, to get the time updated. Still don't know how and when the auto time of day sync is being triggered....?

      If the time would have been out of sync for 1 or 2 hours, talking about full hours, I'd say it's the timezone, again (but why). But as it is automatic, and I do not have a connection to a cell, I'd assume it should just be kept as is?

      A time shift of (1 hour and) 50 minutes is weird, leaving away the full hour(s), due to possibly timezone as just said, the 50 minutes either mean: 10 minutes late, or 50 minutes ahead. Thats weird. How come a phone shifts time of day, during one single night, by that much?

      I haven't checked the date, I'll put a date/time widget on the home screen now to have that in sight too...

      I can't understand what's going on. Timezone is auto, but with airplane mode on, there's no possibilty to update it, so I'd expect it's kept as is.
      Weird is a state-of-the-art smart phone in 2024 not being able to keep time of day running when switched off one sole night. 10 mins is too much, 50 min's topping that.

      Any advices please? Thank you

      Unfortunately, I don't have a solution. But I would rule out airplane mode as a source of error:

      I always have my phone in airplane mode at night, completely turned off or in BFU after auto reboot. Never had such a big ofset regarding the time.

      Yesterday, when I switched the phone on, after being off during night, time of day was 1 hour and 10 minutes behind. Again, that's weird, leaving out the one full hour, there's again 10 minutes of time that it is behind after one night.

      As I already stated, the timezone should not change, if there is no connection to a cell. Is that right, or is that not right? If it is not right, why should the OS change the timezone, if there is no reference (= no cell) for it?
      Assuming the timezone is not changed, which I cannot answer as non-dev, why does the time shift over night by more than one hour? Once 1h10min, another day 1h50min.

      I'd really like to hear opinions on a possible cause. The phone was $1000, so is there an issue with the hardware? Do I have to get it replaced?
      Wipe/reset and re-setup everything from scratch (uffff) without knowing if it helps?

      10 days later

      Once again, today the time was 2 hours and 50 minutes behind, over one night.

      I set the time zone manually to see if it is the issue, but it was not, it did not change anything, the time is that wrong.

      No clue what to do, seems my phone is "broken" and no one else in the world is affected. I'm thinking about to factory reset, but afraid of setting up everything from scratch again :-(

      Phone was off for one or two days. Switched on, time of day was eight hours and thirty minutes behind :-( Timezone, date were ok. Battery too.

      What's keeping the time running when the phone is off? Proprietary firmware, or the OS?

      What's keeping the time running when the phone is off?

      A hardware clock, which appears to be quite inaccurate in your device. That's not normal. The hardware clock isn't expected to provide much accuracy while turned off though.

        Time zone is a configuration value. TIme/date are a single thing: a time counter kept by hardware. It's less accurate when the device is powered off. If you leave it off long enough, it may completely lose the time which the OS should handle by doing something like resetting to the build date of the OS on boot before it's able to fetch the time.

        GrapheneOS A hardware clock, which appears to be quite inaccurate in your device. That's not normal.

        Hmm. Would that be a reason to get the device replaced? If the phone'd been off for a long time, battery drained, etc. then well ok, but I mean, time of day being off for more than 8 hours in one or two days is, yeah not normal. I think that's not a so much unusual use case, even in 2024 ;-)
        But how to do that? Ask the seller to replace it? I assume they'd see some evidence.

        6 months later

        On my p8 time has always been an issue, with various discrepancies, sometimes over an hour sometimes negligible differences. Everything date/time is always automatic, i do toggle the radios on/off quite often. But that does not explain the messdd up time for me, as my p5 never gave me trouble with time, being used in identical pattern.
        time.gov always reports my clock is off for at least 15 seconds.

        24 days later

        On my Pixel 8 Pro I would turn on airplane mode, turn off the WiFi and then power off the phone before going to sleep. Then when I would turn it back on in the morning the time would be off by as much as 2.5 hours. A year later I get a Pixel 9 Pro XL and do the same thing and when I turn it back on the time is off by about an hour. Is this worth returning the phone over and what could be causing this to happen in both phones purchased so far apart and bought at different locations?