Complex sentence: Jimmy's last performance with the band was at Greenbelt 2009; he was replaced by new guitarist Joel Atkins, who played alongside Kuvey untill the band's finish in September 2010.
Split into simpler sentences: Jimmy's last performance with the band was at Greenbelt 2009. He was replaced by new guitarist Joel Atkins, who played alongside Kuvey until the band's finish in September 2010.