as in all or at least most things of this ilk ...it depends.
1. One's file being complete, scored, reviewed, 3Qed.
2. One's nomination circumstance, timing, and your year's competition among nominating pools.
3. USNA's objectives, targets, and consequent applicant pool.
To the degree applicants and their families are conditioned, expectant, and anticipating similarity or predictability as they might with a secular institution, this process can frustrate and/or surprise accordingly.
In a word or several, it is very difficult to scoop or anticipate, and with notable exceptions is not readily predictable. And the longer one watches this, the more this becomes reality. Generally, with the occasional confirming bits of information that can and should encourage, the best one should expect is patience and peace in the process.
btw, nom was notified late Nov, appointment received early Dec, and local students w/ LOAs received in Sept, were both appointed in March. Neither stayed. Anecdotal, but illustrative that in the end, LOAs sole value is lending some of that postitive feedback and assurance that IF one becomes 3Qed and a nom secured, they'll be appointed. And these are most often to keep high priority candidates ...race, ethnicity, athletics, occasional intellectual brilliance, sex, etc. ...on the line and keep USNA among their ongoing evoked set of options.
And this kind of counsel is cheap, easier when looking back on the process, and worth every cent it costs to receive it. But more often than not, it is USNA's to know, yours to wait on the Lord and the Navy, whichever returns first. ;-) Enjoy this time of anticipation. While it may not seem so, like Christmas' coming, for the successful looking back, it'll bring fond and happy recollections. For the unsuccessful, they'll not bother as it'll be of no matter.