Rosalind, no - not a double A. The answer to 43 A took me ages - ithe answer there is very American! (It involves a name and a double definition, I suppose.)
I am getting crosser and crosser as have got the meta but still can't do most of the unclued ones. or see how the ones I do have re hinted at!
Never mind, can't help being slow. 50 ac is very odd indeed