New to the site… bronchiectasis, Pseudomonas and Tobramycin

I just found this group…. Here’s my story:
Diagnosed with MAC in 1997 (detected early). 2 rounds of treatment over a total of 3 1/2 years eliminated it. No recurrence since, but other infections have been present, with progressive damage to lungs evident on CT scans. Lots of antibiotics over the years, minimal use of steroids.
Use Afflo vest and neb Perforomist twice a day, 7% saline daily. Also Spiriva inhaler and Albuterol as needed.
I’m 80, weigh 97 lbs, swim laps daily up to 40 minutes, walk at least an hour daily, do yoga, occasionally bike and basically arrange my life around my lungs.
Cough frequent, very productive (@ 1/2 cup of ugly dark sputum daily, occasionally with frank blood). Colonized with Pseudomonas, which became resistant to Levaquin 7 years ago. IV Ceftazadine reduced severity, but didn’t eliminate infection.
Started a trial of nebulized Tobramycin May 1st - 28 days on,28 off. I last coughed up discolored sputum a few days into treatment!
The effect has been stunning…. No coughing, great energy, I find it hard to believe. I haven’t been able to lie on my back in 20plus years, now I can swim the backstroke!
Has anyone else had a similar experience? How long can one stay on Tobramycin? Aside from the yucky taste, I have no side effects.