Board Thread:General Discussion/@comment-3574574-20180425194423/@comment-91424-20180425194943

Who says it never grows? He probably just cut it regularly, alone (like he did in 604) or with Belle's help. As for when he turned back into a scaly Dark One, well, it was probably part of the transformation: Emma's hair turned white when she became a dark one, so a change in hair length doesn't seem too implausible.