I'm so sorry you're going through a more classical presentation of CF, but it's good that you're putting the info out there, so that we people with this "mild" mutation set take better care of ourselves. As it's easier to prevent than to cure a progressive disease, anyone not feeling symptoms yet should still get strong, exercise and seriously consider taking Kalydeco (which I've been taking for almost 3 years now).
I started getting a chronic cough in my late 30's from MAI, but it wasn't horrible, and I had only had a couple cases of pancreatitis. Things slowly worsened over several years, but still not terribly bad. Just occasional night sweats and a small spot of sputum every day. When I started taking Kalydeco, my sweat test dropped to a completely normal score of 13, and I stopped coughing every day. I only have an occasional cough for a few days every 3-4 months, and I still test positive for MAI, but the levels have gone way down; it lives in the small spot of the lung it damaged, but it hasn't spread. I consider myself very lucky because without treatment, I would have gotten to where you are by the time I hit 50. But with a little bit of lung damage, I'm not totally out of the woods taking the Kalydeco, though; scarring is irreversible. If I had been taking it since childhood, then that would be a different story.
Hopefully, your story will encourage the people with these mutations who haven't gotten sick yet to take Kalydeco and exercise anyway. Prevention is so important.