I don't know about now, but some years ago there were 29 speed cameras between Newcastle and Edinburgh on the A1. Not all were functional, but some certainly were.
I used to trunk that road overnight, and in the end lost my licence for 6 months (and hence my job) for doing more 50mph with an artic on a 60mph single carriageway road at 2am.
The cameras were set at 66mph. The truck's limiter was set at 54mph. Then they reset them at 54mph for trucks and coaches. Got caught twice on the same night that they reset them with a lot of other guys before we realised what they had done.
Then again i got caught twice more in a force 9 gale by two cameras just a mile apart. I was doing 50 & 51mph. It wasn't the truck's speed that set 'em off. It was the spray from the truck.
Still got done though.
When they offered me my HGV licence back I told them where to stuff it. I'd already bought my boat.