May the korban Pessaḥ be eaten on upper floors?

Abstract

The Talmud Bavli, Pessaḥim 85b-86a seems to conclude unequivocally that Qodashim Qalim, including but not limited to the Qorban Pessaḥ, which may be eaten in the entire city of Yerushalayim, may only be eaten on the ground floors: Rav said: The roofs and the upper chambers were not sanctified. But that is not so, for Rav said on the authority of R. Ḥiyya: „There was [only] as much as an olive of the Passover-offering [to eat], yet the Hallel split the roofs!“ Does that not mean that they ate on the roof and recited [the Hallel] on the roof? No: they ate on the ground and recited [it] on the roof. Yet that is not so, for surely we learned: „You must not move on after the Paschal meal to the aftermeal (the ‚Afiqoman‘)!“ and Rav said: „[That means] that they must not remove from one company to another?