I might have the terminology wrong.
But l thought if the patio has been privately developed (PD) being the patio, can you privately develop over the patio again with a decking frame?
How do you work out the ground level from where this decking has been built please?
Looks like a nice neat job...hard to see ground level under that lot, what height is the deck relative to your ground level at the house (looks like a terrace so ground level won't vary that much).
And critically, let's say the deck is actually 600mm above ground adjacent to the house. Would it make any substantial difference to the overlooking if the deck was dropped to 300mm above ground? If not (and looking at that pic I suspect there would still be overlooking) then the bamboo hedge is probably a better use of yr time and effort