Ah, the magic of single barrel bourbon.
I have had several bottles of the ETL. I think that they all came from two different barrels. I cleared off the shelf after I opened the first bottle. It tasted much like you describe. I still have one of those open, only one pour out of it.
The second barrel, I have had several bottles of as well. Completely different whiskey. Enormous cookie spice presence. All the other notes are overwhelmed. They are there but they take a back seat to the cinnamon. I once left a glass with a few drops left in the bottom and nosed it for a week. The cinnamon never faded. Finally, I filled the glass with twelve oz of coke. I could still taste it. It will be a sad day when I run out of this. I wonder what happened at Buffalo Trace the day they bottled this.