SB,
I think you'll find that at least some of the numbers you have quoted are the target figures for the whole redundancy period.
Now whether they will "front load" tranche 1 in order to achieve exits as fast as possible I don't know, but would be surprised if it included numbers as high as you have indicated. One would have to ask what is the point/need for tranches 2 and 3 (I realize it is not just about aircrew...!!) if you are going to achieve all your planned redundancies in tranche 1......