The old folks always tell you to hang a pheasant till the feathers start falling out and its usually green by then
I hang all my birds at least a week.
I killed a few turkeys just before Christmas and hung them for between 5-10 days before we ate/cooked them.
But as a little experiment I hung one right through into the new year for 30 days.
I don't bleed or gut them before hanging, they just had their necks dislocated and the blood collects in the neck cavity.
They were hung in the conservatory and the temperature has stayed between 0 and 10 centigrade during that time, no temperature control, just hanging in a cool shaded area.
I just removed the fillets and legs rather than do the whole plucking and gutting thing, its a lot easier!
The head/neck area did whiff a bit but not as bad as you would think, the rest of the bird looked just like the rest of them did after hanging a few days, i did open up the intestines after I was finished but nothing out the ordinary smell wise in there.
Definitely a more tender meat when hung but never noticed any difference between hanging for 10 days or 30