He is allowed to overtake the red car. But when he wants to merge into the right lane, he has to give way to the red car.

So: when the red car is driving slow enough, he can overtake it and still merge safely, without breaking any rules concerning priority between the two vehicles.

These 2 questions have the same lane reduction sign. In Q8491, the answer says the car on the free lane has Priority, but in Q8242, the blue car on the closure lane can overtake the red car, is it contradictory?