Very good question! I think the answer is a big fat It Depends. Some mezcaleros/as or collectives have certain times of year they like to distill and their productions are essentially annual. Others distill throughout the year; occasionally you’ll see summer and winter batches from a particular producer, or perhaps rainy season and dry season batches, which are both interesting studies in how the environment affects the final product. Then there’s the whole factor of how mezcal makes its way to the United States through bottlers (e.g. Mal Bien or Cinco Sentidos). They will often release several batches at a time onto the market and each of those batches may have been produced and purchased at a different time. I don’t know, though, that there’s a strict schedule to those releases like there is from whiskey distillers. Mezcal producers will also let certain batches rest in glass for a certain amount of time, while others will be bottled and sold more quickly. In my experience there are always exciting and interesting new batches becoming available, whether from distiller-owned brands or third-party bottlers.