Extensive research has revealed that there is a new Gatso on a high 4 metre pole. As well as speed, its camera can spot use of phones and non use of seat belts across 8 lanes and as far as 200 yards, and it is described as indestructible.
Sadly, the "Gilets Jaunes" have damaged or destroyed 80% of French speed cameras, so with fewer tickets to worry about, they're looking at the backlog of old unissued tickets for foreigners, which are now enforceable due to reciprocal agreements. Strangely, nearly 50% of speeding tickets are for foreign cars.