Moed Katan, Chapter Two, Mishnah Two
This mishnah is similar to yesterdays mishnah but deals with the production of wine instead of olive oil.
1) Similarly, if one had his wine [already] in a cistern and mourning or some unforeseen circumstance befell him, or workmen misled him, he may draw off [the wine], complete the process and seal [the jars] in his usual way, the words of Rabbi Yose.
2) Rabbi Judah says: he [may only] cover [the cistern] with boards to prevent it from turning into vinegar.
Section one: In this case, someone has already pressed his grapes and the juices have run off into the cistern, and for some reason he was not able to jar the wine before the festival. According to Rabbi Yose, since the process was started and it was not his fault that he could not complete it, he may complete the process during the festival. He may remove the wine from the cistern, finish squeezing all of the juice out of the grapes and put the wine into jars.
Section two: Consistent with his opinion in yesterdays mishnah, Rabbi Judah does not allow him to complete the process. Rather, all he may do is cover the wine in the cistern so that it does not spoil.