another pointer(!) is that BBC use the nautical standard for identifying left and right channels.

so left = port / red
right = starboard / green

this is “backwards” to most other equipment outside the BBC (so were their mixer faders until recently). the other meters show stereo separation which TBH isn’t as relevant for digital broadcasting and is a hangover from Band II FM broadcast where overloading this side is bad as it can cause undesirable interference on the TX (into the comms of aircraft!)

a lot of BBC stuff is nautical, Broadcasting House/Auntie was considered to be a “ship”. and ships are always female and supposed to be looked after well, but sadly the current trend seem to be “treat the old girl roughly, and when she is half scrap iron send her up North to be broken up”, which is exactly what the idiots in govt seem to be doing to our national broadcaster 😥