Jehovah’s moral standards = 2 people of the opposite sex who stay overnight without a chaperone are guilty of fornication/adultery. There are not 2 eyewitnesses yet under WTS doctrine, these people can be disfellowshipped. But if the circumstances were the same but during the day = not disfellowshipped, because we know sex never happens during the day, right?
See current elder's mannual