I heard that was the new protocol, to start Amikaycin after 6 months with no conversion to negative. I can't give you any advice, I can only tell you how it worked for me. Amikaycin was just accepted as a drug when I started it a few years ago.
The Amikaycin gave me a sore throat and difficulty talking. The doctor's finally cut me back to every other day even though there was no change in getting consistent negative tests. I was on four other antibiotics besides the Amikaycin. How sick are you is something you have to ask yourself, how badly does this affect my life? For me, Amikaycin maybe support for healing for me, but not the deal breaker as surgery was. I have read other people say it was a deal breaker for them and didn't need further treatment after that. NTM CAN come back even after years of remission. My life has changed forever because I will always protect and watch out for possible regular exposures. It's taken 5 1/2 years for me to see the light at the end of the tunnel, this round at least. One can only hope for no more. But I've learned to live with it, I'm much kinder to myself and maybe I needed that. Guess, I am just stubborn and didn't want the NTM to beat me, that's why I went with adding more drugs, even though I've struggled with concern about the side effects. It helps to have a doctor really care about you. I know he wants me to beat this almost as much as I. And thankful he's in my corner. Keep learning and adding into your life preventative measures, be kind to yourself and know that you have a friend in your corner that understands.

Do ACT 3 times a day. Might help.
And pray for healing, that never hurts.

Best,
Cheryl