A possible bug with planes.

So I am playing as syria on one of the new 4x speed maps, and I believe I have found a bug. Note that I have not gone through with this, just noticed I am able to do it.

With Peace Periods before the game we can not attack with anything. We can, however, set planes to patrol an area. And you can set a plane to patrol over the area controlled by another country, and that is exactly what happens, even without being able to attack.