I thought eggs stayed good for upwards of a year. - Snoofy
Three months MAX. And I've raised my own chickens for about 20 years.
Snoofy, here is how to tell if an egg is still good.
put it in a bowl filled with water.
If it sinks, it's good.
If it sinks but stand upright on the bottom of the bowl it is still OK to eat.
If it floats....throw the egg away.