[Stuart]

It’s a fantastic studio, studio b just love what it can achieve and it’s versality, I’d like to see if the presenters can come upstairs to the ground floor, Huw almost tried that on the first day, well he got to the staircase

One of the weather presenters (Matt Taylor) went up there once on a Tweet video to show that part of the mezzanine is certainly stable enough to support weight, but I don't think it's very wide.  The staircase ends in the lighting rig, so actually goes 'nowhere'.

I can't imagine the mezzanine ever being used as a presentational position, as I don't think the LED screens in that upper area are particularly high resolution when close up (I know there is a technical term for that, but I don't know it off the top of my head).