Kentucky Rum Runners Apple Brandy Cask Finish

This bottle started out as the "standard" Doctor Bird, which is to say Worthy Park pot distillate aged in Moscatel casks, then was treated to a secondary aging in recycled apple brandy casks before being bottled at 60.3%
In the glass it has a clear, slightly pale golden hue to it. Swirling gives you nice, thin sheeting, dropping skinny, moderately fast moving legs.
The nose has the trademark ester-y Doctor Bird base aromas of pineapple, banana, and citrus, with that malty funk lurking underneath. The secondary finish on this is very subtle compared to the other limited releases I've had. There's not a lot of big, rich brandy or pronounced apple notes. You get little hints of it here and there in the form of fleeting scents of poached apples, phantom-like whiffs of caramel, and some nebulous sweetness. You really have to go looking for them, though. Using a splash of original Doctor Bird in a second glass helped me zero in on them. On its own you may be hard-pressed to suss them out.
On the palate it has a nice, light mouth feel, with a bit of astringency on the finish. The higher proof doesn't shock the tongue but it definitely puts some heat into the roof and back of your mouth as it goes down. Again, having some original bird as a control helped to point out the differences. The Apple Brandy cask finish is a little sweeter, more concentrated, and sharper, with some hints of brandy finally appearing late on the finish, but it hasn't gone through the transformative evolution like the PX, Old Fashioned, and Paxarate finishes did. Those were definitely elevated renditions of the original - like a sports car that's been modified and tuned by a bespoke autohaus to be a track weapon - The final product more than the sum of its parts. This one unfortunately feels more like the same sports car, but with the gold trim package and a couple bolt-on parts from the dealer. There are some little asthetic improvements here and there, but it's pretty much the same car.