To my experience, lots of flyaways maybe due to strong interferences of WiFi signal (check WiFi channels with FF6 inboard diagnostic page in settings option change to 5,8 GHz when needed),
or to magnetic interferences (metallic frame concrete used as take off spot or car roof or hood, calibration process made in the car to avoid wind, calibration made with a ‘smart watch’ on your wrist that combine both WiFi and magnetic interferences, take off from a table made of wood but with a metallic frame and steel screws, fly near a bridge that always have a metallic frame embedded with lots of electric wires that carry electricity from one side to the other side of the river...).
This latter interference can be avoided by the use of a manual cheap compass in the take-off or calibration area.
Some experience in threads of this forum to support that point.