I don’t know much about them, but I would bet that caramel-forward note comes from a high-extract aging, possibly in smaller barrels. This is where the craft industry is at the moment. Lots of stock in barrels under 4 years, but not a lot of older stock (because most of the distilleries aren’t even 4!).
The whiskey degrades and extracts the wood lignin components into the spirit. Over time these acids link up with fatty acid esters to create the flavors and aroma of a standard aged whiskey like biscuits, tree nuts and marzipan. In the younger stuff you are tasting those free extractives which taste of raw oak, caramel, vanilla and treacle. I don’t think anyone ever intended them to be, but these younger whiskies have really created an entirely new class of spirits with a set of flavors that would never have been released to the consumer. Pretty remarkable time for distilled spirits.
