By 2003 certainly, but I heard that people had contacted O'Brian himself, so that must have been much earlier. It is true that a lot of scenes would not have been possible in the 1990s or earlier.

I like CHH. It was fine for its time and probably the best that could be done then.

Forester himself wasn't so accurate in his writing as POB was.
POB had his weaknesses too, so much as I love his books, I would rather not compare them :D