When I spray BT I always let the frames dry out first, this way they do not mold.
Place the super of treated frames in an upside down outer cover and a sheet of news paper between each super, then top off with another outer cover. Just a super in a plastic bag will not protect them from miss mouse. I had about five supers I had treated and stored in my Mom's garage, forgotten for twenty years (according to the date on the newspapers) and they looked as good as the day I extracted them.