Complex sentence: Craig Welsh replaced Horatio Agar on drums in Sept 2007, and forming member and co-songwriter Pete Sellers left the band and was replaced by Dom Beckford on guitar in May 2008.
Split into simpler sentences: Craig Welsh replaced Horatio Agar on drums in Sept 2007. Forming member and co-songwriter Pete Sellers left the band and was replaced by Dom Beckford on guitar in May 2008.