Andrew Gertler’s AG Artists is expanding. The management company has brought leading client Shawn Mendes’ longtime A&R Ziggy Chareton on as a partner to co-manage the Grammy nominated artist, as well as two new artists: Lauren Spencer-Smith and JP Saxe. Chareton has worked at Island Records since 2011, most recently as head of A&R, which he’ll continue in addition to joining Gertler in management. Rising singer-songwriter Spencer-Smith has been searching for new management since May after parting ways with David Ehrlich. In February, Spencer-Smith (who competed on American Idol in 2020) signed a record deal with Island and Republic Records after breakout hit “Fingers Crossed” took off, becoming a Hot 100 top 20 hit. Saxe is behind the 2019 Grammy-nominated smash ...