The cutoff day is basically right before the day to report. Looking through past years, I have seen late May appointments. And same with Prep School and Falcon Foundation. But, yes, everyone should hear something by April 21.
I will echo what I've learned in past years by asking similar questions here myself....Anyone else should feel free to correct if I'm not correct, or feel further illumination would be helpful.
There's no official application for prep school grants. (Falcon Foundation Scholarship, in this case).
You'll be chosen, or you won't hear anything regarding prep school, either the on campus prep school, or the outside schools that are affiliated with Academies and approved to accept sponsored students into their Service Academy Prep programs. DS is at MMI doing their SAP program as a self-prep (I'm sponsoring him
). And it's essentially like a one year "major", at MMI.
If you have the unfortunate outcome of being "unselected " to USAFA, that generally means not selected for FFS as well. But, there are plenty of cases of receving that selection at a later date as well.
Our experience has been, that self-preping is definitely been "the way to go", towards gaining appointment in later round of applications. Others might suggest State U, or the like, with ROTC. For my son, especially at one of the 6 "Major Military Universities". For us that would have been either Norwich University, or Texas A&M this coming fall. But nothing wrong with ROTC programs elsewhere either, for your plan "B", straight out of HS, or after a yr or two at a Service Academy Prep program school. (PM me for more info on which of these....DS went to 2 yrs of these...diff schools, and I have strong opinion that you should SELF-PREP where you can ROTC simultaneously, ie., Accredited College).
Best of Luck!