I flew to Toronto in Jan. It was scheduled to be a 788 but for some reason when I got to the plane it was a 789. Anyway I sat at my seat, which was 6A but then someone from BA counter came up to me, looked at my passport and handed me a new boarding pass. Asked if I wanted to move, I said sure, it was for 2K. So CW service sitting in a first cabin. One advantage is that the blankets they provided were the first ones. So if too hot you got the pashmena and if too cold you got the thick white first one. Which is great.
But I will say the seat wasn't very clean. Hope that helps.