I'm running an APMcopter SITL with DroneKit/MAVproxy. When DroneKit is "flying" in AUTO mode in the SITL with an 8 waypoint mission, the following function calls returns fine, but fail to actually change the current waypoint. I've confirmed that the next(value) property setter does get invoked, it just doesn't actually change the current waypoint onboard the copter nor does it change what the next() getter returns (it was waypoint #1 before and waypoint #1 after the below function calls).

        MyQuad.vehicle.commands.next=5
        MyQuad.vehicle.flush()

If I do a set_mode command after changing the value of next and doing the flush(), the current waypoint will indeed change to #5 as intended. Welcome any thoughts :)