7 down Bird and dog get lad confused (two words) 9 letters
B- - - -e - - - -
12 across cat ran in to shake off some sugar ---c - o - e
21 across recovering last queen a lot of land -- h - -- y
Thinking about it, I believe the grid is 15 lights wide so to have any symmetry the maximum length could only be (7) with a blacked out light in the middle.
Well done Caran.