Doubling the recipe.
I roast chicken parts in a 350 oven for one hour. The amount of parts doesn't change the cooking time.
For a large quantity of parts, I'd do separate pans for the white and dark meat, as the former will be done before the latter. Makes it easier to manage. Only other advice is don't crowd your pans - to roast properly, the parts need air circulating around them. (The pieces will shrink a bit as they cook, so a couple of inches of space is fine; just don't pile them, or they'll steam/stew instead of getting that crispy roasted skin.)
To add to the good advice you've already received I will just say, "it's done when it's done". Zen but true. Use an instant read to check the temperature of the larger pieces. For poultry that should be about 160F.
Thanks for all the good advice. I will be Zen and taking breathing room while I cook. Thank you!