Does anyone know what the postmark stamps mean on a letter or where we can find out? Backstory is that MIL received an anonymous letter with copies of mean stuff SIL said about her on Facebook. I have been blamed because only the week before I added SIL on Facebook. It’s turning into quite the drama and as much as we try and ignore it we are being continually dragged into it. All the in-laws live interstate and have been told that there is no way to track where letters come from; however that doesn’t seem right to us. The postmark on the letter received reads: HRMC MLOCR 544 01MAR. We assume it means “Hunter Region Mail Centre” and 1 March but have no idea what the middle letters and numbers mean. Does anyone know? Also if we posted from Brisbane Northside would it say something that points to it





