פירוש על עבודה זרה 14:4

In reality, the sages who respond to R. Ishmael are probably the same sages whose opinion was in the first mishnah. Still, the Talmud perceives this format to be repetitive—why repeat their position twice? Thus it must be that there is some halakhic difference between the two positions. The Talmud will now take various disputes that appeared above or will appear below and claim that the sages of the mishnah disagree on these points as well.

The dispute between the two opinions is over whether the three day period includes the festival or does not.