When talking about timelines that go beyond merely a few years, it is actually quite common to use an approximation. Best example, although perhaps a little extreme, is what we know about the dinosaurs. We are told that they died out "65 million years ago". Do you really think that the actual figure is that exact? Of course not. Now scale that down to the "200 years" that we spent in stasis, and you can quite easily assume that this is also an approximation. The other fact that we have to consider is that if the devs told us the exact date (which I think is actually 2284, which is 207 years after being frozen), they would then be committing to a far more specific date in relation to other events that we know of, nearly 4 months before the game ships. Perhaps they still want to keep this under their hat.
It was actually during an interview with Pete Hines, and the way he said it suggests that we start off as a 35 year-old, and then continue roughly 200 years later. This would make sense if you look at it in the context of my example above.