I think that even if the book doesn't update, that mostly goes for the events. There's still a bunch of information about the characters are world that's much more static and less prone to changing even with the butterfly effect. A lot of that information is probably not all that useful to her, but since she's inevitably going to get caught up in things, that information will turn out to be much more relevant, and could offset the book not updating. It would make her need to change her approach in using it, which could be interesting.