It is safer and simpler to cook the frozen turkey when it is still hard frozen, juicier, too. That is how I do mine since I tried it. For next year, from the USDA:

Cooking an Unstuffed Turkey from the Frozen State
It is safe to roast a turkey from the frozen state; however, it will take longer than a fresh or thawed bird. To determine an approximate cooking time, consult a timetable for oven-roasting a whole turkey. Use the timing for the size turkey you have; then add 50 percent of that time to the original time. (Do not smoke, grill, deep fat fry, or microwave a frozen turkey.)

Roasting time is approximate, so check the turkey often toward the end of the estimated cooking time. Insert a food thermometer in the innermost part of the thigh when it has defrosted enough to easily insert one. Cook to an internal temperature of 165 °F. The turkey is safely cooked when the food thermometer reaches a minimum internal temperature of 165 °F in the innermost part of the thigh and wing and the thickest part of the breast.

Giblet Packages. Giblet packages and the turkey neck may be found inside the turkey cavity and/or tucked under the flap of skin at the front of the breastbone. When the turkey has sufficiently defrosted, the packages can be removed carefully with tongs and/or forks during cooking.

If the giblets were paper wrapped before being inserted into the turkey cavity at the plant-which is the case with most whole birds-there is no safety concern if they cook completely inside the bird.
If giblets were packed in a plastic bag, and the bag has been altered or melted by the cooking process, do not use the giblets or the turkey because harmful chemicals may have leached into the surrounding meat. If the plastic bag was not altered, the giblets and turkey should be safe to use.

Do Not Cook a Frozen Turkey in an Oven Cooking Bag or in the Microwave. It is not recommended to cook a turkey from the frozen state in an oven cooking bag. It is unsafe to open the bag to remove the giblets during cooking because scalding may occur. Also, spilled juices and fat may cause an oven fire.