Change to the above info for Amazon. Amazon claims they will no longer use the USPS or similar for deliveries. They intend to open their own competing delivery service in 2020. Until then, above info is correct.
Monday through Saturday there is always mail service... Nationwide. Some days you will get 10 pieces of mail, some days you might get just 1. And every so often you may not get any, but the carriers are always delivering. Sunday is Amazon delivery day where only packages from Amazon get delivered. Regular mail is always Mon -Sat.
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