I've always been a "leaving" man myself. I brought it up on another thread earlier this year but was always taught to say everything in the present sense, i.e. leaving, climbing, turning, passing, lining up etc etc
Everyone has mentioned the descending case, so what about climbing. I.e.
ATC: "Qantas XX climb FL390"
Me :"Climbing FL390, leaving FL370, Qantas XX"
Is that not OK?
TL