I have to say the facts of this case are somewhat extreme. 

A developer gets planning permission for 12 flats, 15 bedrooms in total, in Earlsfield part of Wandsworth Borough Council but decides instead to cram in an extra 5 bedrooms.   Clearly the lure of extra profits was simply too much for him. 

Even worse, he managed to cram in two flats in the basement which is part of the flood plain and already those two flats have twice been flooded. 

But my goodness has  he paid the ultimate price.

He has now been ordered to demolish the building and replace it with a  compliant structure by October this year. 

It is difficult to understand quite how the developer thought he would get away with it especially in the age of social media where sizeable infractions such as this are bound to go viral. 

Also, how does he think his next planning application will go down?

I would have to assume the developer proceeded against the best advices of his professional team, at least one would hope so. 

As for the Council, surely the lesson has to be extra vigilance early on. Unscrupulous developers may well decide to cloak themselves in the anonymity of an SPV and then you have a right mess on your hands. 

Last point - I cannot see how 15 flats were sold when they were blatantly in breach of planning?