The rear fenders are cut lower than the fronts by design to allow more room for the fronts to turn.
Specs the Bentley Manual:
Measured from the bottom center of wheel to the bottom of the wheel arch
Standard Suspension Sport
F - 604mm 23.77 inches F - 589mm 23.19 inches
R - 570mm 22.44 inches R - 554mm 21.81 inches
You add in ~ 3- 3.5 inches for tires and you are spec on.