Good question. Beer, wine or champagne you'd assume it kept fermenting. Whisky rye is distilled and the alcohol is too high so not this. The temperature diffe

Good question. Beer, wine or champagne you'd assume it kept fermenting. Whisky rye is distilled and the alcohol is too high so not this. The temperature differences will cause the pressure in the bottle to have changed each season, maybe the air was absorbed into the liquid, like you carbonate beer. Then with water ingress and a weaken cork it popped, then it bubbled out at the surface.