The biggest difference to me is that a wet brine makes the skin soggy. You can do it a couple days before, but then you still should let the skin dry for another day.
Here's what I do for whole chickens and turkeys:
1. Spatchcock the bird the day before. (
https://amazingribs.com/more-techni...-science/how-spatchcock-and-butterfly-poultry) and remove wishbone.
2. Dry brine. (
https://amazingribs.com/tested-reci...-brining-easier-and-less-wasteful-wet-brining)
3. Place the bird on a rack over a tray and put in the fridge overnight.
4. Mix herbs and spices with a stick of room temperature butter.
5. Rub butter mixture under and over the skin.
6. Smoke indirect at high heat (350* or higher) to 165* in the thickest part of the breast.
7. Slice and eat right away. Resting just lets it get cold and the skin soggy.
Note: Birds absorb smoke like a sponge. Have a clean stick fire or use only a small amount of wood if using charcoal and chunks. For the turkey below, I used one chunk of cherry wood, about the size of a D battery and it had plenty of smoke flavor.
The following 15 LB turkey took less than two hours at around 375*: