How to override default airfield taxi & spawn points

[Ataros]

Try placing AI takeoff waypoint:
1) closer to centre of the new airfield than the old airfield, or
2) inside the new airfield radius only but not inside the old airfield radius, or
3) on a new runway only but outside of the old airfield radius.

Try placing other small airfield objects on spawn points instead of aircraft.

Hope something of these works.