I have set WP_YAW_BEHAVIOUR to 0 which means that the copter should Never change yaw.
In the copter version 3.6.12, when I used to set WP_YAW_BEHAVIOUR to 0 and explicitly set CONDTION_YAW, the yaw would change to the desired degree.
I have upgraded the firmware to 4.1.5, when I did the same, the yaw is not at all changing.
Is it the expected behaviour?