I'm hosting Thanksgiving next week and I have noooooooo idea what I'm doing! I'm going to follow this recipe: http://shewearsmanyhats.com/2011/11/mayonnaise-roasted-turkey/ for my turkey, but I'm not sure how long to cook it.

I have a convection oven and will have a 20(ish) lb turkey. Any suggestions for cooking times??? I've seen everywhere from 3.5 hours to 7! I'm sooooo worried I'm going to overcook it or not cook it enough or it will be done HOURS before we're ready... help!