We got our chicks last June from McMurray. In June, the birds are hatched on Saturday and arrive on Sunday. We notified our local post office of the chicks arrival date.
Our birds arrived on Sunday at the main postal hub for our area, not our local office. Luckily, an employee there contacted us so we could meet to get the chicks.
So my suggestion would be to contact not only your local post office but also the main hub for your area too. Maybe someone will be working at the main hub and would contact you so the birds don't sit around.
If you used a credit card to order, McMurray's charges the card when the birds are shipped. They will come in a cardboard box with excelsior in the bottom.
Save the shipping box incase you have to use it as an infirmary for one of your new chicks.
If any of your birds arrived injured or don't look like they are going to make it, contact McMurray's 800# within 48 hours of arrival and they will credit you for them. If you got them vaccinated, they will also credit the vaccination costs for those birds.
Make sure your brooder is up to temp before the birds arrive. Have feed and water set up too. As soon as your birds do arrive, dip their beaks into some vitamin/electrolyte water. Put them into the brooder immediately.
Watch and handle them frequently and enjoy them!
regards,
keljonma