Went to fill the car with diesel today, popped he remote release for the filler cap, walked around to the back of the car, opened the flap and then..........
Pushed it well past the 90 degree position which I've not done before, only to find that it locks in place with a positive click
Funny, as I'd complained before about it not opening wide enough and flapping around in the breeze as I tried to fill the car.