Wicked Weed Bretticent

Interesting experience with Wicked Weed's Bretticent tonight. I opened a bottle from 4-2-15 first and it was quite funky, lemon sour stuff going on. Then I crack a bottle from 2014 (no month on the label) and the second bottle has a lot more carbonation and way less funkiness. They were stored together since I bought the second. Anyone else have similar experiences with other brett beers or is this just batch variation with this particular brew? Thanks.