In Le Mans, what is that second Timer on the timer board?

In Le Mans, there’s a board at the entrance to the pits.

The first numbers are easy. Its the time remaining in the race.

But the second, I can’t figure out what it is. Seems like an hour, but it’s heavily wrong. Like here it shows 17:03, which is 5:03PM if you don’t know European 24 hour time, but it somewhere close to 4am in le Mans at this point of the race.

So what is that second set of numbers?