On Radio Le Mans on Sunday morning, it came to light that a car that has not done 50% of the leader's laps by a set time (10am or midday ?) will be black flagged. No doubt to stop people rebuilding the car and then just getting in the way. They interviewed a driver (can't remember who) and told him that in order to avoid the black flag, their car would have to do 25 laps in the next 20 minutes
The driver responded that he'd "never heard that before
".