@John-S-Parry said in Strange Turn-By-Turn Behavior:
I created a test route that has a shaping point created after each turn.
This is probably the cause.
From what I recall the algorithm sees "waypoints" higher in priority than the actual turn instructions. Try moving the waypoint at a significant distance before or after the turn and see if that helps. I try to keep them at least 100 to 150m after the turn.