DCIPS uses the leave, benefits, and entitlement programs that are common to all federal employees, to include annual and sick leave, retirement, health and life insurance, etc. In such areas, since there are no DCIPS-unique programs, there are no specific DCIPS volumes written, so DCIPS employees are covered by the OPM and DoD issuances which cover all employees.
In the areas of annual and sick leave, 5 USC 6301 provides definitions for the purpose of Chapter 63 Subchapter I and the Federal annual and sick leave programs in sections 6303 and 6307. The definition of "employee" in that section points to 5 USC 2015, which is the broadest definition of an employee in the civil service. That definition does not specifically exclude DCIPS employees, so the Federal annual and sick leave programs in sections 6303 and 6307 of Title 5 apply to DCIPS employees.
The Combat Support Agencies are part of the Fourth Estate, as defined in DoD Instruction 1402.03 Volume 1 and other places in DoD policy. The Fourth Estate is a collective term that refers to the Office of the Secretary of Defense (OSD), the Office of the Chairman of the Joint Chiefs of Staff and the Joint Staff, the Defense Agencies, the DoD Field Activities, and all other organizational entities in DoD that are not in the Military Departments or the Combatant Commands, except for the DoD Inspector General.
Many of the DoD civilian personnel policy volumes give responsibility to the DoD Director of Administration and WHS for all aspects of personnel administration of employees in the DoD Fourth Estate entities that do not have their own full independent appointing authority, and responsibility in other areas for all of the Fourth Estate. Many of the issuances you receive from WHS will specifically pertain to title 5 employees of DoD Fourth Estate organizations (GS, SES, SL, and/or ST employees), and would naturally exclude your DCIPS workforce because your Components exercise independent DCIPS appointing authority using your own secure human resources information systems. The key is to read carefully the issuances from WHS and DoD Director of Administration to determine if they apply to your Component or not, and to contact the HCMO if you aren't sure.