Han Unification "rules" were an inconsistent mess, but I do know that in Japanese 靑 was at one time a printer's simplification of 青, so you could find either in

Han Unification "rules" were an inconsistent mess, but I do know that in Japanese 靑 was at one time a printer's simplification of 青, so you could find either in texts, and the Consortium tended to encode a character separately if you could find printed examples of both in the same language.