Into daylight and the lead battles for the overall, GTLM and GTD are fully alight.
With the #10 Wayne Taylor Racing Acura leading at the top of the hour there are six DPis still in contention, the top five separated by 30 seconds and the Mazda fighting back and now a single lap back.
The #01 Cadillac had led before a nose change in the pits under Full Course Yellow saw it drop back to fourth before a storming run from Renger van der Zande took the Ganassi car back to the top, taking the slot from Helio Castroneves.
Alexander Rossi though would retake the lead for the #10 as Kevin Magnussen climbed aboard the Cadillac.
In LMP2 the order remains unchanged in the top 5 with Matthieu Vaxiviere currently leading the class in the #8 Tower Motorsport Oreca ahead of a very spirited run by Kyle Tilley in the #18 Era Motorsport car, the pair just 3 seconds apart and well clear of the remaining #82 DragonSpeed car.
Elsewhere there was a further problem for the already heavily delayed #52 PR1 Mathiesen Oreca, the car stopping out on the circuit and bringing out the eighth Full Course yellow. The car is back running but now 43 laps back from the class leader.
The long-delayed Cetilar Dallara that had led into the night returned to the circuit after around 3 hours in the garage for attention to an overheated gearbox.
GTLM continues to be a dogfight, both Corvettes, the #25 BMW and Risi Ferrari have been involved in the lead battle with the #24 BMW not far behind, all five still on the lead lap with the delayed #79 WeatherTech Porsche still 9 laps back.
At the 15 hour mark it’s back to a Corvette 1-2, Nick Tandy’s #4 C8.R ahead of Jordan Taylor’s #3 with John Edwards 15 seconds back in the #25 BMW.
Again no change in the order in LMP3 with the #74 well clear, 5 laps clear of the #33 with the Muehlner Motorsport Duqueine third and a further two laps back
One of two confirmed retirements from the entry in this three hour period came from LMP3, Forty7 Motorsports retiring their #7 Duqueine after an Oil Pump failure.
GTD was another great battle for the led for much of the period under review with Daniel Serra (#21 AF Corse Ferrari) and Maro Engel (#57 Winward AMG) getting very physical at times as they duelled for lap after lap.
The battle would be settled (for now) in favour of the Ferrari with Nicklas Nielsen fending off Philip Ellis, now aboard the AMG, the pair nose to tail.
Third in the order was the #75 SunEnergy1 AMG, still third despite a moment for Kenny Habul on his out lap, the car was soon back on track and lies third at the 15 hour mark.
There was a drama at the Bus Stop with significant contact between Ben Keating’s #97 TF Sport Aston Martin and Ted Giovanis in his #64 TGM Porsche, both would make it back to the pits but the #64 would later retire, Giovanis adjudged at fault for the incident, the Porsche man either missing his braing point or unable to stop and steer the car.
Picture top – copyright Wayne Taylor Racing
Top fives after 15 hours
#10 Wayne Taylor Racing Acura ARX-05c
#01 Cadillac Chip Ganassi Racing Cadillac DPi-V.R.
#31 Whelen Engineering Cadillac DPi-V.R.
#60 Meyer Shank Racing Acura ARX-05c
#48 Ally Cadillac Racing Cadillac DPi-V.R.
#4 Corvette Racing C8.R
#3 Corvette Racing C8.R
#24 BMW M8 GTE
#62 Risi Competizione Ferrari 488 GTE
#25 BMW M8 GTE
#8 Tower Motorsports ORECA 07
#18 Era Motorsport ORECA 07
#82 DragonSpeed ORECA 07
#51 RWR/ Eurasia Ligier JS P217
#11 WIN Autosport ORECA 07
The #74 Riley-Robinson Ligier JS P320
The #33 Sean Creech Motorsports Ligier JS P320
The #6 Muehlner Motorsports Duqueine D08
The #91 Riley-Cox Ligier JS P320
The #54 CORE Autosport Ligier JS P320
#21 AF Corse Ferrari 488 GT3
#57 Winward Racing Mercedes AMG GT3
#1 Paul Miller Racing Lamborghini Huracan GT3 Evo
#16 Wright Motorsports Porsche 911 GT3 R
#9 Pfaff Motorsports Porsche 911 GT3R
#64 Team TGM/ Wright Porsche 911 GT3 R
P44: #7 Forty7 Motorsports Duqueine D08 (Oil pump)
P45: #111 GRT Grasser Racing Team Lamborghini Huracan GT3 Evo (Engine)
P46: #19 GRT Grasser Racing Team Lamborghini Huracan GT3 Evo (Engine)
P47: #29 Racing Team Nederland ORECA 07 (Gearbox)
P48: #20 High Class Racing ORECA 07 (Gearbox)
P49: #81 DragonSpeed ORECA 07 (Crash/Engine)