CSMs love Army Regulations (excuse the paste, from a PDF):
AR612-205:
Appointment and Separation of Service Academy Attendees
Section II
Admission Processing
5. Active Duty Army personnel
a. Unit of assignment. Commanders of active duty personnel who
receive notice of admission to any service academy or preparatory
school will issue permanent change of station (PCS) orders. The
orders will show the selectee’s assignment to the proper holding
facility with duty station as shown in table 1. Regardless of any
authorized delay, personnel will report to the academy to which
assigned on the date in the appointment notice. Personnel will not
physically report to the holding facility cited in the PCS orders as
the unit of assignment. Strength accounting will be done according
to AR 680–1, paragraph 1–7.
b. Maintaining DA Form 201. The holding facility will maintain
DA Form 201 (Military Personnel Records Jacket) (MPRJs). Rec o r d s o f A r m y s e r v i c e m e m b e r s r e l e a s e d f r o m a c t i v e d u t y
(REFRAD) or discharged while attending the service academies will
be forwarded as directed in AR 640–10, table 2–3, and AR 635–10,
table E–1.
c. Pay and allowances.
(1) Active duty pay and allowances will be paid through the day
before the appointee is admitted to any academy. (See DOD Military Pay and Allowances Entitlement Manual (DODPM), tables 1,
2, and 3.)
(2) Lump–sum payment is authorized for unused leave accrued
t h r o u g h t h e d a y b e f o r e t h e a p p o i n t m e n t w a s a c c e p t e d . ( S e e
DODPM, table 4–4–3.) Any advance leave becomes excess leave on
the day before the appointee is admitted to any academy; it may
only be recouped as required by DODPM, program 10305.
d. Personnel accountability.
(1) Personnel accepted for appointment to academies other than
USMA will be reported by the US Army Student Detachment, Fort
B e n j a m i n H a r r i s o n , I n d i a n a , u n d e r o n e o f t h e f o l l o w i n g
headings:Naval Academy, US Coast Guard Academy, or US Air
Force Academy students.
(2) A DD Form 214 (Certificate of Release or Discharge from
Active Duty) will be issued on entry into USMA. Orders will be
issued to transfer the individual to the proper Reserve Component to
complete his or her Service obligation. On the orders, state the
amount of remaining obligation and state that the individual is
currently a cadet.
(3) Service obligation are voided when cadets are commissioned.
(4) Cadets failing to graduate must complete the remainder of the
obligation stated in their relief from active duty (AD) orders
No idea why I remember that AR, but hope it helps. There is info in that AR regarding reserve and national guard Soldiers, too.