Healing to a save point removes Ren's wings.
I think this is because healing to a save point removes all status effects.
It seems you didn't think of adding an exception for wings so may I suggest to fix it now please? :-)
isnt the skill to uncase them free to cast?
Yes, it is. But having to release them again every time we heal at a save point is annoying. It would not be if you add an exception for wings to the script which removes all status effects upon healing at save points.