In real life, at 16-24 knots, the helicopter will attempt to stabilize from the change in relative wind over the rotor system. The helicopter blades (followed by the helo obviously) will climb, but also raise the nose as it seeks equilibrium. When passing through ETL, the cyclic must be directed further forward to counter the nose-back tendency while the power required for flight will drop. Often power will be left as is, as the power required for IGE hover applied in forward flight will allow for both steady acceleration and continuous climb as well to cruise speed/altitude.