Hello Mini owners!
To tell the truth, I have never run out of gas in my Cooper S.
It has hit the light, and i casually went to the station with no urgency.
When I fill up, I take a little extra time to make sure she's extra full.
In Europe they take accuracy seriously. So, take your light to mean what it says, start looking! It's not worth testing to sit on the side of the road for an hour waiting for a AAA truck.
In my opinion, I say 10 miles past the light is right.