Factual error: In "What Happened to Frederick", Kathryn learns about David's affair and confronts Mary Margaret at school (after taking her anger out on Regina), where students and teachers are milling about. Later, she apologizes to Regina for "what happened yesterday", whereas Emma, earlier that day, seeks out Henry at school. Kathryn leaves Storybrooke the same day, and mysteriously disappears. According to Kathryn's phone records in this episode, she disappeared on a Sunday. However, the day she left, and the day before, was a school day. In the U.S., school classes are not in session during weekends. (00:38:25)