There is no doubt that the Van Winkle family uses "limited" supply to create the cult following of the ORVW and various Pappy's, but I do believe that there probably are limited quantities of mature bourbon. This would be especially true for the 20 and 23 year runs. There was no crystal ball in the early 90s that would have allowed them to see how much Pappy they would have to produce to meet demand.
Maybe Julian Van Winkle and BT are barreling more PVW to make it more readily available in the coming decades. But then again, an ample supply would mean more sitting on the shelves, which really would lessen the "mystique" of the brand. So who knows....
There might be some trickery. I discovered that in my area of Dallas TX, the liquor stores didn't receive any allotment of the 2011 version of WLW. I bought two bottles from two different stores and both were the 2010 release (based on proof). I asked the managers of both locations and they had just pulled them from the box. Further evidence was that the remaining brands that came with it (GTS, THHS, and ER17) were all 2011 releases.
So, does that m an BT held on to an allotment of 2010 WLW because they knew there wouldn't be enough 2011 to go around? Or did the distributors make the swap when Jim Murray announced that the 2011 WLW was one of the top whiskey of the world.
I have heard of this practice with the Pappy products.