First off, if you’re reading this as it’s being posted, congratulations. Because this likely means you are a dedicated endurance road racing fan or observer. Or, alternatively, you’ve had too much caffeine. If it’s both, you’re probably at Daytona. Overall, it means you’re a TSO reader/subscriber, and for that, we thank you.

But alas, 2:30 a.m. marks the magical halfway point of the 55th Rolex 24 at Daytona race, even though it means you still have four more hours of darkness (to make 12 hours of darkness) and a full 12 hours of Sebring to go.

At the halfway point, the leads are held by Wayne Taylor Racing (Max Angelelli), Porsche GT Team (Kevin Estre), Performance Tech Motorsports (Nicholas Boulle), and Michael Shank Racing (Jeff Segal) in P, GTLM, PC and GTD.

There have been eight full-course cautions and six official retirements, all from the GT Le Mans and GT Daytona classes (Cars 51, 73, 16, 59, 14 and 24). It’s been cold, dark and rainy but the race rolls on. Track conditions are not good.

The overall lead has largely been held by the new Cadillac DPi-V.R, which has had the measure on both pace and reliability thus far.

Mazda has sustained a setback with an improper wave by penalty assessed to Spencer Pigot earlier in the race but has stayed within a lap or so of the lead. But the second Mazda RT24-P has been sidelined with gearbox issues.

The Tequila Patron ESM Nissan Onroak DPis were hanging in there and may still do so as the race progresses. The No. 22 car led with Brendon Hartley before Hartley and a TRG Porsche collided at NASCAR Turn 1 and 2 (Turn 6 on the Daytona International Speedway 3.56-mile road course). Meanwhile the No. 2 car, anchored by Ryan Dalziel, has pressed on despite an outright speed deficit.

Of the LMP2-spec cars, it’s been the VISIT FLORIDA Riley Mk. 30 Gibson of Renger van der Zande, Marc Goossens and Rene Rast that’s had a trouble-free first half and run in second or third. Electrical and other mechanical gremlins have slowed the progress for the other four cars.

Perhaps surprisingly, and impressively for the debuting cars, there are no retirements thus far in 12 hours. Of course the fact those words have just been typed means that by way of the typist’s curse, a retirement for at least one of them may be imminent in the hours to come.

While Ford has dominated in GT Le Mans, Porsche has impressed in the cooler conditions with its new mid-engined 911 RSR, and rebounded from early race tire issues on the right front. Both the No. 911 and 912 cars have threatened the lead, while the No. 66 Ford has been the best of those Ford Chip Ganassi Racing entries. Risi’s Ferrari has also stayed close to the frame. The No. 67 Ford was delayed following a rare spin by Ryan Briscoe, who caught the curb the wrong way exiting the Bus Stop and went behind the wall for a rear bodywork assembly change.

Corvette Racing saw the hopes for its No. 4 Corvette C7.R go away with a loss of power just shy of six hours, and pitted with a broken lower control arm after being hit by Harry Tincknell’s No. 69 Ford. The No. 3 Corvette remains in with a good shot at a top-five finish in class, but that’s not why Corvette races. BMW’s race has been even more of a struggle, with the No. 24 car retiring early with engine woes and the No. 19 Art Car unable to make much of an impression.

Acura’s enjoyed a strong run thus far with both of its NSX GT3s, and the respective orders of Andy Lally, Katherine Legge, Mark Wilkins and Graham Rahal in the No. 93 car, and Jeff Segal, Ozz Negri, Tom Dyer and Ryan Hunter-Reay in the No. 86 car. The sports car full-season drivers will get more driving time than the IndyCar regulars, owing primarily to size and their regularity in double stinting and occasionally triple stinting tires.

Lexus has also led on debut with its new car, the Lexus RC F GT3. Jack Hawksworth, another driver with a recent IndyCar past, took the No. 15 car to the lead not long before suffering a deflated right rear tire, the damage of which ruined the right side quarter panel and sheered away the bodywork. It required a replacement of the right side door. That was the only 3GT Racing car running because the No. 14 car retired early with Scott Pruett losing control through Turn 2 and hitting the wall.

So that takes care of the two new cars in the GT Daytona class. How ’bout the others?

Audi, Mercedes-AMG, Ferrari, Porsche and BMW have all led in class. And Lamborghini and Aston Martin, which haven’t, have also run in the top three.

So while we could make a formal rundown of who’s done what in GTD, it’s best to let the race play out for another few hours and check back in with who’s on the lead lap when the sunrise occurs.

The spec Prototype Challenge cars keep on trucking along, as almost indestructible cars. Both Starworks cars have been to the garage, at least one of the BAR1 cars has spun, and so has the Performance Tech car. But Performance Tech has largely controlled the class lead from pole with its quartet of James French, Pato O’Ward, Kyle Masson and Nick Boulle.

IndyCar update: All eight full-season drivers confirmed for 2017 have run.

Sebastien Bourdais led for quite a bit in GTLM in the No. 66 Ford. Tony Kanaan called his Ford GT debut a “blast.” Scott Dixon has had fun while hailing the competitiveness of the class. Rahal has led in GTD, and Hunter-Reay’s been in the top five. Spencer Pigot and Conor Daly have got some laps in in their Mazda and PC cars, while James Hinchcliffe’s been unable to get much running with gearbox issues.

Townsend Bell’s Audi incurred a severe penalty of more than four minutes from IMSA for an improper wave by. You’ll have seen that term before and asked, “What does that mean?” In layman’s terms, when a car in the same class is ahead on the track of the leader in that class – say they’re running fifth or something – and a caution comes out, that car can take a wave by to gain a lap back. But in Bell’s case, a miscommunication over the data at the team’s disposal triggered a call to attempt a wave by when the car was not eligible to do so. That’s left that car several laps back outside the top-10 at the moment.

Other past open-wheel drivers like Christian Fittipaldi, Joao Barbosa, Scott Sharp and Ryan Dalziel have also impressed this race.

More updates to follow later on in the race.