Reference for Rosh Hashanah 42:3

אמר אביי ה"ק על כולן שלוחין יוצאין מבערב על ניסן ועל תשרי עד שישמעו מפי ב"ד מקודש

The following was cited as conflicting with this: 'Messengers go forth to proclaim six months'!<span class="x" onmousemove="('comment',' I.e., whenever the month is lengthened to thirty days.');">⁴</span> - Abaye replied: What is meant is this: For all [the other months] the messengers set out while is is still night,<span class="x" onmousemove="('comment',' On the thirty-first day, since it is already certain that New Moon will be on this day.');">⁵</span>

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