Sad to say but I may have been caught today. Would be my first speeding offence if it comes through. I was in a 30, came off the dual carriageway slip road thinking it was a 40 (turned out it's a 30), it then goes into a 30.
As I joined the main road from the slip, at the top of the slip, I saw the policeman with the speedgun, another policeman next to him, their car parked in the corner barely visable and I think two other coppers on the footpath. I didn't brake harshly but I did tap my brakes and after that I was not near 30 but above it by around a few mph. I passed them but no-one followed. I then proceeded to turn around and see what their line of sight may have been, and if the gun could point down the slip road. Turned out they were catching people off the flyover/slip, but they couldn't see down the slip unless they were further down the road. By the time I got there they were gone.
I will have to wait and see.