I just spoke with a PC Kieth Lehey of the CO11 Public Order Planning Department to ask if they had a better map of the SOPCA zone than is on their website:  http://content.met.police.uk/Article/Organising-a-protest-march-or-static-demonstration/1400002380711/1400002380711.

He told me that the SOCPA zone had been repealed as of 31 March and no longer applied.

I double checked by asking: so there is no legal prohibition on protest on responsibility to inform the police of any demonstration?

No, he replied, but it's always a good idea to let us know...

What have I missed?