I was an elder for over 20 years. In that time I probably participated in about 50 judicial committees. Not one involved apostasy.
They were all either about sexual issues, drugs and or alcohol abuse.
I do know of one elder I used to serve with that stepped down in 1995/6 and refused to say why. The CO tried to force him to share his reasons with all the elders at an Elders' meeting. He just kept his mouth shut.
Later I learned it was about the change in the "generation" teaching.
By that time I was in another congregation and I never did find out what happened to him. I hope he faded successfully.