I ordered a refrigerator part (main controller board) the other day, and I really need it before something bad happens to the fridge. It was sent via Priority Mail, but USPS's well-built tracking page doesn't have an expected delivery date. Provided it takes 2 days to get here like most Priority Mail, it should get here tomorrow. So... does anyone know if Priority Mail is delivered on Saturday? I would assume so since it's USPS. I would be very disappointed to know that I can receive a bill on Saturday but not a part I really need for my refrigerator.