Fiba lane violation interpretation

[Travelling Man]

If you are questioning whether:
1) the player's foot was extended into the lane but NOT touching the surface of the floor while the ball was in-flight.
or
2) does the simple action of the foot 'breaking' the vertical airspace constitute a lane violation?
I'm imagining how this would work, the ball is in-flight by ft shooter, the opponent steps into the lane but keeps the foot off the surface, but it may appear that it was on the floor.