Well, which physical day, is actually irrelevant. If you think about it, we're not computers. We aren't turned off, and then turned back on. So which day, really isn't important. But for the Air Force academy, they start on thursday, the 24th. And they will have basic training until July 25th. (Saturday). They will then march back out of the field, and back to the main academy campus. They will spend the rest of Saturday, Sunday, Monday and Tuesday getting settled in their room, getting their books for classes, computers, and all the other things required to be a cadet. On Wednesday, August 4th, they will have "A" (Acceptance Day). And they will start classes on Thursday, the 5th of August.
Could they have started on another day? I guess they could have. However, all the students start their cadet classes on Thursday the 5th. I suppose that the academy worked backwards and said: How many days do the new cadets need to get ready FROM the end of basic to classes starting. They then backed up to that date as the day BCT would end. They then counted backwards 38 consecutive days, and made that the first day of BCT. I guess you'll have to look at the army, navy, coast guard, and Merchant Marines to see if they have the same length of BCT and when they start classes.
FWIW: My son and daughter's high school started the new year on a Thursday. It allowed a couple days before classes for teachers and students to resolve scheduling and other conflicts. It allowed just 2 days that week to get settled in and familiarized. So starting on a thursday is not actually uncommon.
