Recent update to 11.0.6 (kernel: Linux 6.1.74) on Pi4.
UK (nor any of the constituent UK countries) is not listed in Settings/Interface Regional.
Jersey and Isle of Man are in the list - so to is Ghana, which is also on GMT.
BUT even when set to one of these countries I get a Four hours error.
Timeserver #1 is set to 0.uk.pool.ntp.org. #2 to 0.uk.pool.ntp.org and so on.
I must be missing something!