Complex sentence: It was reformed in May 1947, within No.11 Group, as the School of Land/Air Warfare in May 1947 and became part of the Joint Warfare Establishment in March 1963.
Split into simpler sentences: It was reformed in May 1947, within No.11 Group, as the School of Land/Air Warfare in May 1947. It became part of the Joint Warfare Establishment in March 1963.