Stationary planes spawns and spawn bugs

[JtD]

If a stationary plane gets destroyed, it no longer works as a spawn point. The only scenario I can imagine is that there is a default spawn point on the same spot the stationary plane is at.

I think logic is like that:
- players per base as determined by number of default spawn points of the airfield
- 1st choice for spawn point: stationary plane like players choice
- 2nd choice for spawn point: generic stationary spawn plane
- 3rd choice for spawn point: default spawn point

Essentially, if all stationary planes on a base are destroyed, it works like a base that never had stationary plane spawning. Feel free to share the mission.