I don't know; but I believe you need to buy it now and stick in a pot of water and in the fridge to defrost.
there's no good reason to cook a turkey for 6 hours, or even 4- it'll likely end up dried out, it takes up the oven for the whole day, and you can accomplish superior results, in much less time, using either high heat in the oven, or by using the grill/smoker. here's two options, each of which is better with a brined bird. if you don't want to brine it yourself (and you can use a dry brine, which is even simpler), just by a kosher turkey- it's already been brined, and it will never have been frozen. take said bird out of the refrigerator several hours before you want to cook it, and let it come to room temp. if you've got a kosher bird,, it may smell a little sulfurous when you take it out of the bag. this is normal- just rinse it off. also, if kosher, it may look a little weird, since they trim it some. this won't matter once it's cooked. if using the oven, make sure the oven is clean, or you'll end up with a lot of smoke. place the oven rack in it's lowest position and preheat to 500 degrees (really!) place the bird on a rack in a large metal roasting pan suitable for high heat. a foil roaster won't work. do NOT stuff, and do NOT tie the legs together. once the oven is preheated, stick the bird in feet first (away from the oven door) and roast for ~45min. then check to see how it's browning. if it looks too brown, cover loosely w/ foil. otherwise continue to cook until done, which should be ~165 degrees. the temp will rise as it rests. total cook time, depending on size of bird, will be an hour and fifteen minutes to two hours. when it's done, take it out and let it rest for a good 20 minutes, to as long as an hour. carve and serve. if you want to smoke roast it, start with the same bird, and then follow aaron franklin's instructions here: https://www.youtube.com/watch?v=2zWHOEkBLAg&list=PLao-l5N_oBWNxKs0ghVoH9mCLzHRkl0SV it boils down to ~2 hours at 375. i've used both methods, and they're both good. i happen to like smoked turkey, so if i had a grill, that's what i'd do, plus it keeps your oven free, and house from free from smoke.