MAVSDK (C++), in Follow me mode drone is always heading north

Hi,

Running the follow me example provided with MAVSDK C++, the drone is always heading north whatever the follow me mode is (front, behind etc.) and whatever the track of the drone.

For example, I was expecting same heading/track with behind mode and opposite heading/track for front mode.

What am I missing?

Monitoring with QGround Control with Stream GCS position set to never
Ubuntu 18.04, MAVSDK 0.39, JMAVSIM (same behavior with Gazebo)
Same behavior with MAVSDK-Python

Thank you for your help.