I went 100% 24/7 fluent for around 11 years at a point of my life, even during emotional situatios (e.g. exams or arguing about life-changing topics). Sadly, something happened and my brain reversed to stutter, but I had been so extremely stressed out prior that rarely anyone experiences that. Also, the current stutter is very mild in itself and milder than what I had as a kid before the recovery. There are different cases and not everyone can be cured, but I am hopeful about my case coz if I could be totally fluent for a decade, I can do it again