Sam I Am: Columbia Mgr./Regional Promotion West Coast Sam Borenstein has joined Jason Owen's Sandbox Entertainment to handle day-to-management for Kacey Musgraves and Charlie Worsham. Borenstein joined the label more than two years ago (CAT 8/18/14) after two years at Stoney Creek and three in artist management with Jordin Sparks/Cozy Touring. Reach her at 615-915-5454 or here. Back at Columbia, the opening was actually posted earlier this month (CAT 5/3) and is still listed here.