Irritatingly I may have got close to the end with this one but I'm stuck on two clues which don't have an extra letter in them. I have -A-C-N-Y for 18dn in the left grid and -E-O-N- for 8ac in the right grid. There are plenty of words which fit these patterns but none of them seem to correspond to any wordplay or definitions in the clues.
I would grateful for any hints or errors pointed out.
I'm also puzzled as to where the extra"L" goes. Both 21ac in the left grid and 24ac in the right grid seem to be candidates.