I've also heard that Asia is consuming more and more tobacco at premium prices. So part of the shortage may be the result of products being shipped elsewhere, declining quantity of quality tobacco leaf also plays a role (see McClelland). When products do come in stock there's a bit of panic buying or FOMO that exacerbates the issue. One can weather these periodic fluctuations by keeping an eye out in the B/S/T threads, I use Turbotin to let me know when favored blends come in stock at any of a large number of retailers. Of course, liking a blend that is always available can help tide one over.
