I use starter all the time with my birds from hatch till death. I mix with broiler and add Nutritional yeast to it. I can't get much in the way of feed here and I like non GMO so that even limits me more. If they are getting so much green I can't see them having a problem with angel wing. Id either mix with maintenance or finish it up. Just keep an eye on things if you see anything that looks out or ordinary on the wing it's an easy fix when they are just growing out their wing feathers.