Section 4538 - Additional authority(a) No provision of this subchapter shall be construed to preempt or supersede any other program relating to milk or dairy products research organized and operated under the laws of the United States or any State.(b) The provisions of this subchapter applicable to the order issued under section 4533(b) of this title shall be applicable to any amendment to the order. Pub. L. 98-180, title I, §137, as added Pub. L. 99-198, title I, §121, Dec. 23, 1985, 99 Stat. 1372.