I'd do just what you're planning to do.
The only thing I could add is that I'd store it in a conditioned area inside the house, not in the attic or garage or shed or something. If you're going to do that, I'd take care to wrap it up in a couple layers of garbage bags and duct tape it up. That'll keep the wood from overdrying and causing warping and shrinkage problems.
Depending on the humi's construction (material it's made of), it may not matter at all. Being that humis rely on close tolerances for a tight fitting seal, it's always best to protect them from extreme temperatures, dampness and very low humidity.
