Most around here say they will hang two weeks if they have room, but during the busy season they are cut when they come around in the cooler, usually 7-10 days. I have only found one place that will hang 28 days. The USDA inspectors hate to see the hanging carcass turn green, but this one place is able to do it. Some places also determine hanging time by the fat cover, a carcass with a thin fat cover will dry out if hung too long.