Pre-Yom Kippur, the daf was Zevachim 17a, and a brayta records Rabbi Simai’s remez / hint to the idea that a tevul yom who performs avodah, those rites are disqualified:
Three Weirdnesses in Rabbi Simai's Remez
Pre-Yom Kippur, the daf was Zevachim 17a, and a brayta records Rabbi Simai’s remez / hint to the idea that a tevul yom who performs avodah, those rites are disqualified: