"...The FY 2012 National Defense Authorization Act (NDAA), Public Law 112-81, enacted 31 December 2011, authorized the military services to offer early retirement to Soldiers who have completed at least 15 years of active service. This is a discretionary authority and not an entitlement. The Army has elected to use this limited program as part of a comprehensive force management strategy to shape the force. It does not apply to Soldiers of the Army National Guard or the U.S. Army Reserve..."
