There has been a radio message released from either F1 or McLaren and this is the text of it:
Lando: yellow flag, can I go again or not?
Will: No we have to box, we have to box..(some seconds later) Man, I'm sorry, they shouldn't have done that
So Lando could have crossed the start/finish line, started another lap and potentially been higher up the grid than 15th.
It's like McLaren are self sabotaging at this stage. They have the car, they definitely have the drivers but they are getting dizzy at the prospect of winning something after such a long time it seems.