The following link was posted on another thread a few days ago and has some useful/interesting information:
http://www.usna.edu/AboutAIS/nominations.html#Nomination Reports
The text relevant to your question is pasted below. I surmise from this that if you are nominated and have a high whole candidate multiple than you will get an appointment since the "charging" or "slotting" of candidates to nominating sources looks like it actually occurs after I-day for everyone other than NAPSters.
"How to Charge Nominations
Starting in the end of May, incoming plebes are charged against one of their nominations, even though they may have received and been qualified for more than one nomination.
After the NAPS Admissions Board, all incoming NAPSters with a principal nomination or a Congressional nomination are charged against their nominator source’s vacancies.
Then approximately 170 NAPSters are charged with SECNAV nominations (Regular Navy/Marine Corps, Navy/Marine Corps Reserves). Any remaining incoming NAPSters are charged as Qualified Alternates (QA).
After Induction Day, the process of manually charging the rest of the incoming class is accomplished. Those eligible for nominations from other than the Congressional sources are charged. Then the congressional charging takes place by state.
The Candidate Status by Vacancy (2603) report is run to verify which plebes have not yet been charged throughout the process. After all congressional charges have been made, the remaining plebes are charged as Qualified Alternates. NAPSters may be charged against another nominator source or as a Qualified Alternate (QA) rather than as a SECNAV nomination.
Business Rules used in Charging Nominations
If the nomination is a numbered alternate, charge the principal nominee to the vacancy if the prospective midshipman has accepted the appointment. Otherwise, charge the highest numbered alternate who has accepted an appointment.
If the nomination is competitive alternate to a principal, charge the principal nominee to the vacancy if the prospective midshipman has accepted the appointment. Otherwise, charge the competitive alternate nominee with highest multiple who has accepted an appointment.
If the nomination is competitive, charge the prospective midshipman with highest multiple who accepted appointment to the vacancy. In the case of a candidate having more than one congressional nomination, work with the nomination with the earliest date of receipt.
All nominator sources other than Congressional are charged in the following priority:
Nominator Number of Appointments
Source Allowed per Year
Presidential 100
Vice Presidential 1
Superintendent 50
Regular Navy/Marine Corps 85
Navy/Marine Corps Reserves 85
Honor Military, NROTC,
NJROTC, MCJROTC 20
Children of Medal of Honor winners unlimited
Children of Deceased or Disabled veterans unlimited
Qualified Alternate Remaining appointees"