pekak (along with many people in the world)-please don’t go crazy over the freezer. It’s a difference of a few months. Cheshvan to Shvat or Iyar to Av. Those that want to start to be mekayem the hechsher mitzva of that mitzva kiyumis that you mention is free to do so before he goes into the yeshiva.
Regarding Bein Hazmanim, I heard in from Rav Yisroel Reisman many years ago that Bein Hazmanim is to learn things that you normally wouldn’t learn in a yeshiva setting. For example, a short masechta.
