I don't think that photo accurately portraits the length of the object due to perspective or even possible lens distortion. It may look very long in the photo, but in reality it could be fairly short. Furthermore, we can't know from the photo if it's in the process of being raised and retracted: for all we know, it's only partly through the process of being stowed away.
Well, the screen shot is a frame from the CCTV4 video. I know it is not distorted by the width and height of the CCTV logo. But distortion or perspective don't play a role here.
The ceiling, the floor and the wall where the seats are mounted reach to the same point where videographer stands (the focal plane of lens) regardless lens perspective or distortion. This means the ceiling is as long as that many seats, way longer than the partition's height. Even if part of the ceiling is the partition, the question regarding the space above the other part is still a big question. I would have asked the same questions to C-17 if I found a photo of it like that.
Anyway, maybe an answer comes up in the future.