I grow turkeys for the Thanksgiving market, and schedule them for processing 4-7 days before Thanksgiving. After processing they are water chilled, drained, and bagged so they take the desired shape. Within a few hours they stiffen, but they are already in "market shape". Over the next few days, in the customer's fridge, they will pass through rigor mortis and become the most tender turkey they have ever eaten.
Yes, the joints are sometimes stiff, but they loosen in stuffing and roasting. If cutting up for smoking or frying, just work the joints. I've never had a stiff turkey after 3 days.
For my Cornish X broilers, they go same as the turkeys, but a day or two less. I generally bag and freeze them right away, then when planning a meal I pull the bird out 3-5 days early. Despite the fears of people who have only experienced grocery store birds, they won't spoil in the fridge in this amount of time.
The only tough bird I ever did was my first home-processed Ameraucana hen. She was about 5 years old and chewing on her was like chewing a tire. The dog thought it was a chew toy when I gave him the meat. I did everything wrong, including roast her while in rigor mortis. Live and learn!