PLATT’S NEXT PLATFORM: With the Sony/ATV-EMP deal now done, attention turns to the exiting Big Jon Platt, whose last day at EMI is today. Don't believe all the chatter about him making a deal with Roc Nation. That’s just Rumor Mill fodder based on his great relationships with Jay-Z and his incredible team. He’s definitely headed to a major. The big question is, will it be a publisher, a record label or a combination deal that allows him to do both? (6/29p)