Thanks malone, but I'm not sure.
I was trying to find some logic like that - but it would need all 3 of the As to be somehow 'seated' on the Bs.
If you know what I mean . . .
I've completed it but the whole thing seems unsatisfactory. Why is 30d not shaded in green, or 11a and 22d? They seem to be just as thematic as the ones that are unclued. Why have some without definitions and some without clues at all, when the answers seem to be fulfilling the same function? It seems arbitrary to me.
I agree! Nothing clever here! 2W, 2M, 2F, 2B....so what! Is there a meant to be a final twist?
....Apart from the fact that random green M no.2 could contain 'R' or (in Chambers) 'I'