If no category needs those spillover visa numbers, it will most likely end up with the most retrogressed country. But at this point of time, we don't know how the EB-2 ROW and EB-3 ROW will pan out. I suspect EB-2 ROW will yield to EB-2 India but I'm not sure about EB-3 ROW. The CO already told there are thousands of EB-3 ROW pending.