If it is for a new drama, a short-hair look/different hairstyle maybe necessary or better...for acting as a professional .
But for WS anime, no need for a short-hair style as we all remember...after 3 years apart, Joonsang & Yujin reunited at their dream house, Yujin was wearing long hair.
To match with this scene, should be a long hair look.
However, if there is a wedding afterwards as a happy ending, it should either be keeping long hair or a new hairstyle for a bride, anyway !! haha