I'm glad that this topic has been brought up. We've never hung any of our pork but one thing that we do, is to try and time having our weaners so that they are slaughtered in the late autumn or early winter. We do this to avoid any problems with flies.
Two lots of weaners ago, we did do some in the summer and it was a nightmare to butcher the pigs while at the same time trying to keep the flies off them. By choice, we try to get our weaners in and around August so that they get some sun and warmth on their backs before being slaughtered November, December time.