@SandreS it was one time during setup and it also can use Windows location services. But once we know your location within a minute, we can tell you if the sun is overhead at noon - or not!

We do all our internals in GMT/UTC so if the sum of time zone and wall-clock time is correct, it should keep working.

Here is a tester script to compare with our server:
https://justgetflux.com/timesync.html

So yes, if "UTC time" in the OS is wrong, we will transition at the wrong time.

We only use tz changes as a cue to adjust location (like for traveling between timezones), but cancelling this dialog is just fine too.

We are sorting results by population - for now can you use "City of Worcester"?

We stopped using Google Maps with their 15x price increase so we aren't as good as we used to be with figuring out "which" name is meant when someone types a query.