For me there was never an actual "time when I first found out".
Rather, it was a creeping realization that happened over the years, a realization dulled by the routine, by the JW social life with many nice people, by the feel-good moments, and of course by that wonderful in-built "sanity protector" called cognitive dissonance.
It probably started when I was a child, when I couldn't buy into, let alone explain to anyone else, the fragile arguments about why we didn't celebrate birthdays, although other types of anniversaries were fine. Over the years the things I couldn't explain to myself, let alone to others, increased.
It was lots of little things really. An increase in earthquakes being a sign of the end? Why didn't anyone else see that we were merely living in a time with an unprecedented level of monitoring, reporting, and communication of seismic activity?
Reporting of field service hours? Simply not a Christian concept, and I don't recall them even trying to justify that one with a scripture. That just didn't fit with the spirit of Christianity at all.
And so it built, all the little things I couldn't believe, until I simply knew that I didn't agree with the religion I was practising.
Perhaps the biggest "moment" for me was realizing that my having been dunked in water at a convention was not a legal contract with anyone, and that Elders Tom, Dick and Harry had no right to tell me what to do.
The feeling then was one of empowerment, plus the slightly daunting challenge of responsibility for making my own decisions going forward.