38 U.S.C. § 7421: Personnel administration: in general

Notwithstanding any law, Executive order, or regulation, the Secretary shall prescribe by regulation the hours and conditions of employment and leaves of absence of employees appointed under any provision of this title in positions in the Veterans Health Administration listed in subsection (b). Physicians. Dentists. Podiatrists. Optometrists. Registered nurses. Physician assistants. Expanded-duty dental auxiliaries. Chiropractors. Any position for which the employee is appointed under section 7306 or 7401(4) of this title. Any determination under chapter 71 of title 5, United States Code, of a collective bargaining unit within the Veterans Health Administration of the Department of Veterans Affairs, and any recognition under that chapter of an employee labor organization as the exclusive bargaining representative for employees in a collective bargaining unit of the Department of Veterans Affairs, that is in effect on the date of the enactment of this Act [ May 7, 1991 ] shall not be affected by the amendments made by this Act [see Tables for classification] and shall continue in effect in accordance with the terms of such determination or regulation. With respect to cases pending on the date of the enactment of this Act [ May 7, 1991 ], or those cases which are brought before the establishment of either an administrative grievance procedure pursuant to section 7463 of title 38 , United States Code (as added by the amendments made by this title), or a negotiated grievance procedure established under a collective bargaining agreement, such cases shall proceed in the same manner as they would have if this Act [see Tables for classification] had not been enacted.”