I was 34. My son was being assessed and the paediatrician's checklist read like a biography of me. Two years of waiting lists later I had a piece of paper explaining my entire life.
Interested in other people's routes here — formal diagnosis, self-identified, still questioning. All equally welcome on this site, as far as I'm concerned. Gatekeeping is expensive and the assessment queues are years long.
Self-identified for three years before the formal one. The thing that convinced me wasn't the deficits list — it was reading autistic adults describing masking and feeling like someone had published my private notes.
diagnosed at 8, so the opposite route — I got to grow up knowing, which I'm grateful for even though school "support" mostly meant a laminated card. the number of late-diagnosed people here who were told they "couldn't be autistic because they have friends" makes me so angry on your behalf
Never formally assessed. I'm 41, I've kept a notebook of locomotive numbers since 1991, I eat the same four meals, and my wife read one article and just looked at me. The NHS wait where I live is four years. I know what I am.