The answer is "yes and no". The AS does have a combination of double action and single action -- but it throws in the "AS" mode on the first SA shot. Essentially the first SA shot retains the same length of pull as the DA shot (approx 0.63 inches). The idea is that the extra distance gives you a "cushion" to prevent accidental discharge in high stress situations. Personally, I never even notice the difference except when I'm dry firing.
After that first SA shot, the trigger will only reset to the shorter (approx 0.4 inches) trigger travel. If you pull the trigger rearward in the AS mode, you'll feel it "click" when you reach this short reset distance (and remain there).
That's what makes the AS trigger system unique - although by and large it is a basic DA-SA system.