Hello. This watch (70's Hamilton Auto) works fine until 23:35. The hour and minute hands stop moving, while the seconds continue to tick. I've had the dial off and watched everything working smoothly. The calendar wheel and it's click all work great when setting - either in set mode and quick-set for calendar. Today I removed the balance and pallet fork and again, everything was smooth when keeping some light pressure on the crown. (Hands never stopped.) However, under extremely light pressure, I can feel increased "drag" when hands get to about 23:20. That light drag continues until the date change at 00:00. After midnight the drag disappears and only super-light pressure is needed to make the hands move. I don't want to open it up again until I get some fresh ideas. Doesn't seem like your basic "cannon pinion requires tightening" issue. No missing teeth on any wheels. Thanks!