8. (1) A Director appointed by the Government shall hold office during the pleasure of the Government. (2) An elected Director shall hold office for a period of three years, shall continue in office after the expiry of his term until his successor is elected, and shall be eligible for re-election. (3) A casual vacancy in the office of the Director shall be filled by election or appointment, as the case may be, and the Director elected or appointed to fill the vacancy shall hold office for the unexpired period of the term of his predecessor: Provided that it shall not be necessary to fill a casual vacancy occurring within three months of the end of the term in which it occurs. (4) No act or proceeding of the Board shall be invalid merely on the ground of the existence of any vacancy in, or any defect in the composition of, the Board.