Yes, DayPilotScheduler namespace is deprecated as is no longer available. Instead of DayPilotScheduler.dragStart() you can use DayPilot.Scheduler.startDragging(options):
Old syntax:
DayPilotScheduler.dragStart(element, duration, id, text);
New syntax:
DayPilot.Scheduler.startDragging({element: element, duration: duration, id: id, text: text});