my god theres LOADS of those high cameras - not GATSOs - just traffic watch or CCTV ones - whats going on? went through there last night (red sv, in a bit of a hurry lol from elephant to byfleet)…couldnt believe how many there were! and the R1 that kept playing with me - cheers - was fun 
They put up a lot of ANPR cameras on most major routes - they stick out a bit on the A3 though.
It’s mainly down to the Pollution Zone thing or so I’ve heard