Originally Posted by ///M Rakete
CBS, or Condition Based Service, determines when your car needs use-driven service like oil changes. My understanding is that CBS factors in things like engine time, engine speeds, and fuel consumed, likely as a bias off of a normal 15k mile cycle. So "heavy" use could drive down the cycle but remember that CBS doesn't know about your 4,200 mile change (you did it yourself or the dealer didn't reset CBS as you would have paid for the early service), it is comparing 8,000 miles with the last known service reset of 1,200 miles. It thinks 6,800 miles have gone by. The car doesn't measure anything in the oil.
I see, so that means in 6,800 miles plus about 14 track days I had enough use that I needed a new oild change. In other words it is really a good idea to change your oil way more frequently than the OEM service intervals if you track the car. I drive conservatively on the street with OK (20mpg avg.) milage, so I asume the continous high revs on the track contributed big time to this.