Perhaps I'm misinformed, but my understanding is that CF is generally detectable early on - most CF kids born before the 20th century didn't last much longer than a year.
Is it possible yours is just an unusually mild case?
Yes I have a "mild case". Though "mild" is a political hot button in the CF community and the phrase "mild CF" can get you lynched in some crowds. The PC term is "atypical CF". Just as they first recognized "classic Kanner's syndrome" as the only form of autism and now recognize a variety of less severe issues as part of "autism spectrum disorder", they also now recognize less severe forms of CF. That certainly contributes to how long I have lived but it does nothing to explain how I came back from death's door.
Is it possible yours is just an unusually mild case?