Complex sentence: W7531 was the second Short Stirling to carry the name'MacRobert's Reply', it was not officially named' MacRobert's Reply', until after entered service in March 1942.
Split into simpler sentences: W7531 was the second Short Stirling to carry the name'MacRobert's Reply'. It was not officially named' MacRobert's Reply', until after entered service in March 1942.