After a week or so, they start to lose viability, but many have hatched older eggs successfully. Store them in a cool place, about 50* to 60*. Keep them on their sides or fat end up. Give them a turn every other day or so. Do a small test batch of about 6 to 12 eggs first, to work out any problems that might arise with using a new incubator for the first time. That way, you don't accidentally make a mistake and lose over a week's worth of eggs. You'll just be out a few days worth, and you can trying again.