Responsa for Sukkah 108:8
ואמר רבי זירא כי הוינן בי רב בבבל הוה אמרי הא דתניא יום הכפורים שחל להיות ערב שבת לא היו תוקעין ובמוצאי שבת לא היו מבדילין דברי הכל היא כי סליקית להתם אשכחתיה לרבי יהודה בריה דר' שמעון בן פזי דיתיב וקאמר ר"ע היא
When I was in the school of Rav in Babylon I used to say that which has been taught, "If Yom Kippur fell on the eve of Shabbat, they did not sound the trumpet, and if it fell at the conclusion of Shabbat they did not recite the Havdalah" is agreed to by all, but when I came up to Palestine I found R. Judah the son of R. Shimon b. Pazzi sitting and teaching that it was in agreement with R. Akiba only?
Teshuvot Maharam
You asked about a community that wished to declare a fast on Monday, Thursday and Monday, and the first fast day fell on Tu Bishvat. Should they be concerned and postpone the fast to the following week or not? Thus my inclination is that the fast should be postponed to the following week, and the fast should not be set because we do not find any fast on Rosh Hashanah.
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