I am not an Insider ...but have been a BGO and been watching the process for almost 20 years. USNA does not have "big drops" like USMA or USAFA , except for a "big drop" of declined letters right after the Admission deadline to those that don't complete their application or are clearly not qualified. (To be honest, I didn't see that this year...both acceptance and declines are trickling in with little rhyme or reason this year). Pure speculation on my part, but I suspect that Noms and Appointments considers each slate as soon as all relevant candidates have been reviewed by the Admissions Board. Some years my candidates hear early, sometime later. All you can do is be patient and worry about what you can control