6v6gt:
OK. Understood. I guess also when the clocks are running in autonomous (missing sync) mode, they should any handle daylight saving time correction etc.
Actually no. They only user interface is 2 push buttons to adjust the time up and down. That's on digital clocks, analog clocks have no user input. Impulse analog clocks won't even run without a master clock, the master clock puts out 24 VDC at 58 seconds after and removes it at the minute to cause a solenoid to advance the minute hand through a series of gears.
There are clocks available that have a DST table in them but the user interface is clunky. The only display o most of these clocks is a 7 segment display, a LCD would be a unnecessary expense that would likely price the clock out of the market.