Variation is the nature of small batch and single barrel whiskey. I believe Brown-Forman actively promotes the idea that there will be variation between batches/barrels of WR and JDSB and I don't hear about them losing customers over it
To that effect, I recently got to do a side by side of our first ever batch of Single Malt (11-1) against the newest (13-2). While I will freely admit there is a difference, I didn't find it to be startling or otherwise disconcerting. The newest batch was an improvement for sure, one I have no doubt a consumer would appreciate. And the first batch was not a bad whisky by any means, I enjoyed both.