Pretty sure that you only get the BAH if the orders are over 30 days (not including boot camp), but maybe that was for unmarried reservists/guard... I got married a month after my last period of active duty in 2014 (AT), but I never got BAH during Boot/SOI or any of my ATs from 2008-2014. I guess I'll ask this question as well, should be going on orders for a couple weeks this fall. BAH in my area is over 3K/month, so its not chump change.
I can't quote any regulations for you but I can say that all my guard and reserve friends at flight school were receiving full time active duty benefits including BAH.