Complex sentence: He was announced as the new editor of the Sunday Telegraph in April 2017, having formerly been deputy editor of "The Daily Telegraph", responsible for business content, and an associate editor at "The Spectator".
Split into simpler sentences: He was announced as the new editor of "The Sunday Telegraph" in April 2017. Since then he was deputy editor of "The Daily Telegraph", responsible for business content, and an associate editor at "The Spectator".