I’ve smoked briskets for 30+ years on my wood burners, but started using a Mak about a year and a half ago. Here’s how I do it based on my personal preferences.
In order to compensate for the lighter smoke flavour of the pellets, I put the brisket on the smoker cold from the fridge and wet from whatever binder (water, mustard, pickle juice) I use to stick the rub. These two factors cause the meat to take more smoke in the beginning.
As you asked originally, I do program the controller to run on Smoke setting for the first 4 hours, which maximizes smoke production of the pellets. I have it programmed to then shift to 225 or 250 (depending upon how long I have) until the meat probe hits 203. Then I have it programmed to drop to 200 and continue running until I stop it.
As the probe reads higher and higher, I might take the temp and probe, and manually adjust temp or stop it when the time comes. But if it hits 203 while I’m still sleeping, or busy, the programming will kick in, drop temp to 200, and hold it until I out there. I’ve found 203 to be a fairly predictable IT for good, consistent results the way I cook.
I plan for 1.25-1.5 hrs/lb, then add a couple hours just in case. Unlike many on this forum, I use holding for the convenience of marrying up cooking and serving times, but I don’t plan to hold for several hours intentionally. In my experience the brisket just needs 30-45 min to vent and relax before slicing. If I do need to hold for a few hours I wrap in towels and put in a cooler.
Re: prep and cook, I don’t inject, marinade, mop, or wrap. IMHO the point of injection is to add flavour, so while I’ll inject turkey or a pork loin, brisket doesn’t need it. Marinade would minimally affect a brisket IMHO, and after mopping briskets for years and watching the mop roll off to mess up the bottom of the smoker, I concluded it’s a long run for a short slide so I stopped wasting my time. I never wrap because I want to smoke rather than braise and I prefer the consistency of the meat, particularly the bark, when it’s naked all the way.
One reason I suggest you try my method is it’s simplicity. If you’re trying to figure out YOUR method to achieve brisket results YOU like, this simplicity — no injection, no marinade, no mop, no baste, no wrap, no foil, no B.P., no hold — minimizes the variables that affect the result. As you gain experience and dial it in and get results you like, you then can experiment by adding and adjusting variables one at a time. Wrap in foil, for example, and you’ll see the difference because you’ll know what it’s like unwrapped.
In any event, good luck and have fun — remember, it’s not magic or rocket science, just smokin meat . . . .