i'll take my same snapshot of the wing when you release the ailerons. You will still have the negative angle of attack due to the continued rotation but now you have no aileron the wing will now be producing 'negative' lift which is going to oppose the roatation and apply a torque in the opposite direction. this force will be created only while the aircraft is rotating in roll. So when you release the ailerons you will immediately have an opposing force to the continued roll that will stop as soon as the aircraft returns to non rolling flight. the speed at which the roll stops is going to be related to inertia in the same way as the wing picks up speed.