The onBeforeEventRender event is called for each item in the data source (events.list) during loading. You can make adjustments to the data item before it is processed by the Queue component.
DayPilot.Queue.onBeforeEventRender(args)
dp.onBeforeEventRender = function(args) {
args.data.cssClass = "test";
args.data.html = args.e.text + ":";
};