Complex sentence: When Congress acted in mid-October to approve Bradley's time in service waiver and promotion to permanent brigadier general, his effective date for brigadier general was backdated to September 1,1943, so that he would still fall where Marshall and Eisenhower intended for purposes of seniority.
Split into simpler sentences: When Congress acted in mid-October to approve Bradley's time in service waiver and promotion to permanent brigadier general, his effective date for brigadier general was backdated to September 1,1943. The September 1,1943 date for permanent brigadier general enabled Bradley to line up with his peers where Marshall and Eisenhower intended for purposes of seniority.