As announced in ALARACT Message 267-2008, new retention control points take effect:

Rank (Total Active Service in Years)
Private (PVT) - Specialist (SPC) (8 Years)
Corporal (CPL) / Specialist (SPC) (10 Years)
Corporal (CPL) / Specialist (SPC) Promotable (15 Years)
Sergeant (SGT) (15 Years)
Sergeant (SGT) Promotable (20 Years)
Staff Sergeant (SSG) (23 Years)
Staff Sergeant (SSG) Promotable (26 Years)
Sergeant First Class (SFC) (26 Years)
Sergeant First Class (SFC) Promotable (29 Years)
First Sergeant (1SG) / Master Sergeant (MSG) (29 Years)
First Sergeant (1SG) / Master Sergeant (MSG) Promotable (32 Years)
Command Sergeant Major (CSM) / Sergeant Major (SGM) (32 Years)

Okay I get the whole time in service thing. I just discovered that I have a RCP date of Jan 2010 and desire to exercise this option but NO ONE will tell me what I need to do or where to go to put in a request or anything. I am a SGT with 15 years and a ETS of May 11, 2012 and I have no desire to become promotable now or ever.

AR 601-280 4-11

DA Form 4991-R (Declination of Continued Service Statement)

AR 635-200

4–4. Voluntary separation of soldiers serving on indefinite enlistments/re-enlistments.
a. Regular Army soldiers serving on indefinite enlistments/re-enlistments desiring a voluntary separation for reasons
not specifically covered in this regulation must submit requests through the SPCMCA to Commander, USA HRC
(AHRC–EPR–F), 2461 Eisenhower Avenue, Alexandria, VA 22332–0478, the separation authority for such actions.