Very unlikely to be ANPR if no plod around on bikes normally.
If no plod was most likely DVLA, anpr operated by plod, where as dvla are by themselves.
Vans rarely marked with any livery,(they don't have to be), but DVLA have to put signs out advising you are about to go past a dvla camera van.
If it's spotted on the road with no tax and/or insurance some ones getting done, and all the better for it imo.
tabetha