Q. We have a well attended Daf Hayomi shiur. Can the shiur take place on Erev Tisha Beav after chtatzot (afternoon) as we usually abstain at that time from learning Torah that does not apply or refer to the churban? Does the fact that a significant amount of bitul Torah (neglect of learning) is involved permit the shiur?
A. Remah (O.H. 553: 2) writes that it is a tradition not to learn Torah on Erev Tisha Beav from chatzos (midday) onward, unless it is the same subjects permitted during Tisha Beav itself.
However Mishna Berura (8) quotes Poskim that permit (Maharshal, Hagra, Chaye Adam and others) since they maintain that it is a unnecessary stringency. Maamar Mordechai, adds that this creates bitul Torah for many, since people learn what their heart desires. He rules that one can be lenient. Shoel Umeshiv (3: 1: 131) mentions that he wrote that particular teshuva on Erev Tisha Beav, since it was necessary.
Horav Shlomo Miller's Shlit'a opinion is similar.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit'a