a couple years ago. I incubated a clutch at normal temps for about 50 days then pulled them out of the incubator at room temp for a few days then put them in a cool room at 60F. until they hatched. 3 out of 4 hatched at about 130 days and all were normal. One had a slightly kinked tail which it probably would have had anyway. I did this because it was thought in some cases that chuck eggs may overwinter and hatch inb the spring in the northern parts of the range. I guess maybe it's possible.