It is autogenerated, find a speedcam on map,modify speed or position then search for file as i indicated Use specific properties from file explorer that you use and you ll see date an hour when you made the changes
Accurate, not really some are some are not
For example in Italy, in every village are 2-3 speedcams, that will announced to driver,but in fact the case of speedcams are empty @BIRBANTE can confirm So ,its about how well do you know the roads,and of course to respect the speed limitsat least for first time
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