Great Policing....for me!

[MalcQV]

Regarding the law and flashing 20mph..

https://mocktheorytest.com/resources/school-safety-zones/

School safety zones

School safety zones are a stretch of road immediately outside a primary school where the speed limit is 20mph and no motor vehicle is allowed to stop or park during school operating times. Different schools have different operating hours, so these times can vary. If the speed limit is 30mph then advisory 20mph signs are installed (the limits in this case are not mandatory), although it can be gently enforced using traffic calming measures.

 

[Jasandjules]

The police know where to set up speed cameras and the council know where to patrol for illegal parking then.
That is what happens at my Grandsons school.

Yes, very true, every week I saw police there with the speed traps. Sadly, on Saturdays only.