popa bar abba you’re right. If a person is a vegetarian because he/she saw shechita and became turned off, if they feel they just can’t eat meat, that’s not an apikores. But if the person says that shechita is just as wrong as other slaughter, that it’s being cruel, then that person is basically saying that the Torah mitzva of shechita is wrong. An apikores is someone who says that a part of the Torah is wrong, Hashem made a “mistake” or Moshe Rabbeinu “decided” on his own and made a “mistake”.
