<p>It will count against their 5 vacancies if they nominate you and you have no other nomination source i.e. Presidential, ROTC, etc. Most MOCs will give a nomination to those with an LOA, but there are situations where they have not, as well. If you have an LOA and no nomination, there is no guarantee that you will get an appointment, unless they give you the VP nom. Put your best foot forward, insure the MOCs know you have the LOA and highlight the reasons why the Naval Academy gave you the LOA to begin with. Obviously you have some superior qualities for them to have given you one.</p>