Ok, so you admit fair enough for the yellow. I'm assuming you were expecting it sooner or later.
To have put it in the middle of the windscreen on the piss like that is like telling the pits to take your money, don't bother with an inspection and send you on your way. But then to only give you 70 minutes is flat out fucking piss weak
Report them on their conduct and follow it right through if you think that will help. Unfortunately, I don't beleive anything will come of it.