Reference for Zevachim 193:4

וכי תימא ה"נ והתניא ר' נתן אומר לא אמר ר"ט אלא זו בלבד

Rather, [the reason is] as R'Nahman said in Rabbah B'Abbuha's name, viz. : Each day effects scalding for the previous one.<span class="x" onmousemove="('comment',' Many peace-offerings were sacrificed during the festival, and the boiling of each day's sacrifice expels from the pot what it absorbed the previous day, and thus it does not become nothar.');">⁷</span> BUT THE SAGES MAINTAIN: UNTIL THE TIME OF EATING etc. What does this mean? - Said R'Nahman in Rabbah B'Abbuhah's name: He must wait as long as [the sacrifice] may be eaten, and then scour and rinse it.

Jastrow