I think the first moment was finding out about adult autism, and that sudden lightning bolt that what I was listening to could be talking about me. It was like looking into a stream and seeing your reflection for the first time, that I wasn't a bad version of one animal but a different animal all along.
Second moment was walking out of doing an in-person ADOS. I had come to it prepared to be open, but wasn't prepared for walking out realising I had never felt so autistic in my life and actually having a word to use other than weird. They hadn't said it at that point, but I knew I couldn't hide it from myself any longer. That was when I joined the forum, as an act of embracing it.
Getting the offical diagnosis helped to cement it then, but for me the other two points of naming were stronger, evoking. The diagnosis was like a tribal tatoo part of the ceremony after the main experience.