Hi,
I just received a IWC GST and the minute subdial at the 12 position fails to rotate over to the next position when the chrono second hand sweeps past 12.
The hour subdial at the 6 position works fine when you let the chrono run for several hours and the watch keeps good time.
Before I contact the dealer is this something minor a local watchsmith can fix or a geartrain problem that needs major disassembly AKA return it for a replacement.
Thanks.