I asked Chris McCubbin, author of the Confederation Handbook, why he had to move the Kilrathi war up to starting in 2638 - his response makes a lot of sense, here it is...
OK, since you asked.
It's the damn Pilgrims' fault. EVERYTHING is the damn Pilgrims' fault. If they hadn't decided to make Blair Pilgrimerific, the continuity could have been a LOT closer to the games'.
Specifically, re. the date of the Iason incident ... OK, Blair's in his early 20s. His parents were both killed in the Pilgrim war when he was a toddler (actually, the script implies he was a bit older, but I fudged). If I stuck with the games' chronology, this means that the Pilgrim affair either *immediately* preceeded the Kilrathi dustup, or they actually overlapped.
So why is that a problem? Well, to me at least, one of the central themes of the whole Wing Commander milieu has always been the resonance with real-world history. Call it the "Pearl Harbor" metaphor. (Bill Fortschen has carried this metaphor sometimes to extremes in the game novels.) The assumption has always been that when the Kilrathi attacked, Confed was big, peaceful, reasonably enlightened and more than a bit complacent - just like the US when the Japanese attacked Pearl. If the Kilrathi had immediately followed the Pilgrim thing, Confed would have been a bit more battered but a LOT more ready. Like America going into Korea. That just seemed wrong, so I juggled the timeline to give Confed a few years' buffer between the wars. (And let's emphasize here that if I hadn't changed the dates, the Pilgrim thing would have still introduced discrepencies into continuity, they just might have been a bit better camoflaged.)
Basically, it was a choice between sticking closer to the chronology of the games, or to the central themes of the games. I decided that theme was more important to keeping the book a "real" Wing Commander experience.
That was my main reason, anyway. I think it's a lot better substantiated than making Angel English and Paladin French (although I think both actors are great).
Again, use this however you want.