Complex sentence: Around late 2014/early 2015 the band underwent a line-up change when their lead guitarist Eddy decided to leave the band, and rhythm guitarist Collins left due to illness They were replaced by Dean and Adam Turner respectively.
Split into simpler sentences: Around late 2014/early 2015 the band underwent a line-up change. Their lead guitarist Eddy decided to leave the band, and rhythm guitarist Collins left due to illness They were replaced by Dean and Adam Turner respectively.