When I had my battle with the local post office I talked to the Post Master (mistress). The first words out of her mouth were that SHE DIDN"T KNOW WHAT RATES SHOULD BE CHARGED! She literally had to go to the book to see what the current rates were and what the rules were. Even after her decision (which was totally wrong) the counter people charged whatever they wanted. I went to the area manager and basically they agreed with me. But at the local post office I was just told that they would put whatever postage I wanted on the envelope. Of course that means people could be getting COD's. Never did get any satisfaction from them. And even today they have no clue. In fact if your PO has one of the automatic postage machines the postage rules on the machine are different than what the counter people use and what is online. Your government at work.