Sounds like you got a real winner for a post mistress! I hope for your sake she's only a temporary appointment or she gets a little smarter. At least you proved her wrong & knocked her down a notch from her 'know-it-all' attitude. It's always amazed me at some of the people who advance to higher positions, although, I'm sure other businesses have the same problem. Some of my friends from UPS tell me they see the same thing there. Never be afraid to report the inept to their superiors. Maybe she's where she is, because others have NOT reported her. Good Luck & don't give up!