The Bureau of Workmen’s Compensation, Workmen’s Compensation Commission, and Workmen’s Compensation Units in the regional offices of the Department of Labor shall continue to exercise the functions and the respective jurisdictions over workmen’s compensation cases vested upon them by Act No. 3428, as amended, otherwise known as the Workmen’s Compensation Act until March 31, 1976. Likewise, the term of office of incumbent members of the Workmen’s Compensation Commission, including its Chairman and any commissioner deemed retired as of December 31, 1975, as well as the present employees and officials of the Bureau of Workmen’s Compensation, Workmen’s Compensation Commission and the Workmen’s Compensation Units shall continue up to that date. Thereafter, said offices shall be considered abolished and all officials and personnel thereof shall be transferred to and mandatorily absorbed by the Department of Labor, subject to Presidential Decree No. 6, Letters of Instructions Nos. 14 and 14-A and the Civil Service Law and rules. Such amount as may be necessary to cover the operational expenses of the Bureau of Workmen’s Compensation and the Workmen’s Compensation Units, including the salaries of incumbent personnel for the period up to March 31, 1976 shall be appropriated from the unprogrammed funds of the Department of Labor.