This question comes up every year and I can never remember the answer. Sir @Rupert.H, perhaps you can pull yourself away from whatever flogging station you’re occupying atm to provide the official answer to this question
To get credit for a tour stage, does the ride have to be “started” before the stage closes or “finished” before the stage closes?
Edit: and similarly, would a rider get credit if they started a stage before it officially opens, but finished after it opens?