It's hard to pin down exactly when I totally gave up on the WT, but I would say 3 years from around that time till my last meeting.
But it was probably about 4 years of it in the making.
Going from not being able to reconcile science and the bible (like the flood) to not seeing how masterbation, oral and anal sex, or premarital sex could in anyway be looked down on by god.
Then not seeing how god could care about who loved who (homosexuality), since 10% of all life exhibits bi or homosexual activity.
To the realisation (this came early) that there was NO holy spirit acting on anyone, or any intervention at all.
To how can god care about zombies, vampires, pokemon, harry potter, (all fake things) and how they could be harmful to people who love god?
To the GB keep changing their tune, and often going back and forth on the same issue.
To having my mind blow of scriptures I read a million times that show that the god of the bible is much more evil than "satan" OMG the horrible death and destruction he loves!
Then the realization that I wasted about 47 years of my life :(
That kinda sums it up.