29b
Bottom line
Why does the gemoro ask this shaale (2 prutos marry, divorce, marry) only according to Bar Pada. The question is equally applicable to ulla and to abaye and rovo (bottom of 28b) they are only arguing about the pidyon after ketztiza. But before ketzitza everyone agrees that you have to keep being podeh, again and again.
Avrumi Hersh, London england
Baruch she'Kivanta! This point hinges on an important dispute among the commentaries. Some actually maintain that Ula does not agree to Bar Pada regarding the automatic resanctification after the saplings are redeemed (see the Ran in his second explanation on 28b, DH veha'Chacham ha'Gadol). According to this, we can understand why the Gemara on 29b-30a tries to resolve the question of Rav Hoshaya only based on Bar Pada, and not based on Ula.
But others believe that Ula agrees with Bar Pada, like you appear to be assuming in your question (see the Ran 28b, DH v'Kasav ha'Rashba). See the Rosh at the end of 29b who explains that indeed Ula would agree, but we are just mentioning Bar Pada's name because he is the one who spoke out this Halachah.
I hope this helps.
Warmest regards,
Yishai Rasowsky