Optical neuritis was the symptom that got me diagnosed! Since then I've not really had many other flare ups, had something smaller happen a few years after. But there's a lot of variables here, we're all different so it's impossible to compare. Just do what you can and let your care team know when anything changes

I'd say about a year and a half after I had optic neurutis I got my first big relapse and that was when I was diagnosed.