Soave -
Why stop there, in the world of Private ownership it has been known for the 12 seat helicopter to be in 8 seat configuration and STILL carry 12 pax - (13 actually, there was one in the co pilot's seat).
Fortunately there was no one counting when they disembarked at Battersea, and no, it wasn't me chief.
I believe they were operating within the WAT though - it was a short flight and a few kids.
G.