What does the X with grey background mean on the vehicle positions graphic? 

Orange is your current position, and green is squad mates. I used to think it marked the next position you'd move to when pressing the button to change seats, but this seems to have changed with the latest update. 

[![Icon][1]][1]

As you can see above, I am currently in position 4, my squad mate is in position 2, position 1 marks a non-squad team mate, and position 3 is marked with the icon. If there were more seats available, only one would have the X symbol. I remember first getting the game and the X would denote where I would move to next (when pressing X on PS4 version conveniently). However, since the latest update this behaviour has changed so my assumption is either wrong, or the patch has broken stuff.

Does anyone know what the X is telling me?

  [1]: https://i.sstatic.net/YzS4l.png