Issue with STICK_MIXING during takeoff

When the STICK_MIXING option is set to “1” Plane 4.0.8 allows me to override controls as supposed. But I am not able to override the rudder when current waypoint is TAKEOFF. Does anybody have ideas what might be a reason for this?

Problem is solved. It turns out that stick mixing is allowed only from sertain speed. Experimentally, I found that this starts at a speed of 25 km/h.