I realized today, that there are dropouts in my 24HR. Checked my watch while driving my car, and hr was "---". I went to settings and it showed "Connected" for my HR Belt. But the HR Belt was in my bag in the trunk.. So it was not measuring any pulse.. Have you experienced it as well?
Yeah, I've noticed the watch can sometimes be reluctant to "let go" of the strap HR. The strap has priority over the wrist, as the electrical data is better quality than the optical data.
I'm guessing that the movement of the car fooled the motion sensors in the HR belt into thinking it was still being worn, and so still transmitting.
At the end of a workout, taking the HR belt off is one of the first things I do, so that it has the chance to sit motionless for a couple of minutes while I rehydrate, etc before driving off. Accessing the HR widget during this time should force it to switch over to the wrist OHR when it can't detect an HR from the chest strap, so it shouldn't then matter if the strap wakes up again.