Dealers go by the 'Service Due' mileage, not the actual mileage on the car.
The 10k, 25k and 40k intervals are approximate mileages and will vary greatly depending how you drive the car, so if you drive like a lunatic all the time your countdown will go a lot more quickly. If your countdown is saying 2,500 miles but your Odometer is saying 1,000 go by the countdown - it proves you drive sensibly and respect your engine!
