Just by way of a footnote...
Never report "leaving" unless that is asked for. i.e, say "Left" or "vacated" as in, we have "Left/vacated" the level. To report "Leaving FL100" DOES NOT mean that you have left that level. It can mean, we are stting the a/c up for the descent/climb etc, but are actually still sitting at it! Be specific! Alas, some pilots do report leaving a level and then take another 20secs-2mins to actually vacate the level.