I doubt many people are going to like this but here it goes.
Shipped eggs are always a gamble. If I get a 50% hatch on shipped
eggs during the spring months I'm happy.
Shipped eggs in the December cold and abuse the boxes get at the
PO during the holiday season is insane. I hope for a 20% hatch on
eggs like these (quail excluded because they do well).
My bators are full of shipped eggs right now, most from
Ebay. I paid
between $4 & $12 plus shipping. I'm even sending out some quail
eggs to a friend this morning.
So, my point is keep your expectations reasonable. In addition, a couple
extra days on the eggs should be the least of your worries.
Best of luck with your hatch. Spring is right around the corner.