2000 Cline Oakley

[Tastevin]

Hello Drew. Could have been malolactic fermentation but that is not usually as lively as you experienced. From a distance, I would hazard a guess it was going through a secondary fermentation caused by a stray yeast having its wicked way with some residual sugar. For one reason or another, all 12 (or whatever quantity is in a complete case) bottles are not necessarily from the same vat/cask. You didn't say, so I guess you didn't taste any - may have tasted quite nice. T