I have played music on and off (piano, violin and others) since I was a kid, but never had perfect pitch.
Now I’m in my late 40s and I’ve been learning and playing the same piano piece almost every day for several months. Recently I’ve found that I can sing the tune at the correct pitch before I start to play - at least the last 10 times in a row that I’ve tried. So it seems I am inadvertently developing perfect pitch - if I can sing one note with absolute pitch, I can work out other notes relative to that.
I’m kind of amazed, because I always thought perfect pitch was something you either have or you don’t, but it seems it can be learned, even at my age.