I know of no one who backs off the valve springs of their lawn mower or seasonal use vehicle. Not even the local race car or motor cycle enthusiasts; though doing so is not a bad idea, I never have in decades of skiing or vehicles; some of which have set for years unused.
I am not a back country bash er of huge forceful deep snow arc's, rocks and trees; thus it is not an issue of ill-safety if ejected.. My bindings are set on the light side; by my ask or deed, lighter than the charts dictate. I am glad to be out of them should I need to be with no knee strain, and have not been released when I should not have been.
I intend to, but have not always waxed before storage. Same wax I will be skiing on; scrapped and buffed or brushed. If not, then simply rubbing wax, any wax even a candle on the edges to prevent rust is good.
Storage is upright on their tails, in the basement many times strapped at the tips, generally with a piece of 1/4" insulation foam between them loosely brake enter-twined. I think it would be best to leave them apart at the midsection; materials, wood or man-made certainly can take a set, and can warp on their own, w/o other influence.