M25 speed camera warning

They seem to have finally finished the anti-clockwise stretch between the M23 and the M26 and the variable speed camera signs are working. Yesterday they were set to 50mph for some reason (no idea why as there were no holdups or workers there - maybe it's because the clockwise section is still being worked on and is under the same speed restriction)

Anyway, on my way back from Essex I saw the cameras almost continually flashing on the anti-clockwise side presumably catching folks who were ignoring the 50 limit.

I was also recently told the speed cameras at the tunnel and the bridge are also working and catching a good deal of motorists. I don't know if that's true but worth bearing in mind.