With WLT tobacco in its poly-Nylon vapor-proof bags, the leaf will maintain pretty much the same case in which it arrived, once the bag is opened, so long as you promptly roll the open end, and clip it (with a clothespin, etc.) after every use. Each time it is opened in a low humidity environment, it loses a bit of moisture. If it gets too dry, I simply pull it all out,
lightly mist the exterior of the handful of leaf (not each leaf) with water, then replace it. It then equilibrates over the next few hours. My goal, when I do that, is to return the leaf to low case, so that it won't fracture when handled. With a little trial and error, you can avoid too much moisture.
If the leaf in the bag has become bone dry, that does not create an issue, so long as it is not handled. To use it as filler, a very light misting and a few minutes of rest will bring it back to low case for immediate use.
For storage of kilned, home-grown leaf, I use 3-mil poly-Nylon bags from Uline:
https://www.uline.com/BL_5563/Vacuum-Bags I purchased a carton of
10" x 30" bags, then split the cost with another forum member. The 10" x 30" bags will hold even my biggest leaf (which sometimes requires folding the tips). The initial cost ($130 for 500 bags--26 cents per bag) seems high, but my half-share of the purchase has eliminated the mad scramble to locate appropriate storage as each batch of leaf comes out of the kiln. Most WLT bags are 5 mil (I believe), but the 3 mil bags from Uline do the job.
Huge hand of Long Red, folded to fit.
Bob