Have not seen a s-duct outlet spoiler like this before.
It's possible this is a grey area that was missed in the rules perhaps? The area the barge boards used to sit in was lowered 150mm and then moved forwards. Perhaps they've taken that to mean the 150mm lowering doesn't apply to the new area 100mm forward from the old limit?
I think it's just a gloss black section that look like openings. Probably trying to hide something or direct attention to this area away from another. Like when they painted exhaust vents on the engine cover and few years ago.
I hope these can cool the engine.
They added an extra element to their mid wing and put that wisker wing lower along with bargeboard regulations, I don't want to say I called it, but they did go in the direction I mentioned.