Is there any way to tell who will be playing Billy in Billy Elliot the Musical in New York this Sunday?

Honestly, no. You can make predictions but that's just it.... a prediction. The producers have made an effort to keep the schedule secret and they've done quite a good job at it. My best guess would be Kirl because he went on Thursday night and it seems that Thursday night performers go again Sunday. Yet it's just a guess. Sorry.