I have used my 5D WIFI PRO to hold Brisket, Ribs, and pastrami over night, I have held brisket, pastrami and pork butts for up to 16hrs with great results, I have held ribs up to 10hrs. If I plan on holding them for quite a while say 8 hours or longer I wrap at normal temp then I finish cooking to approx. 180* then pull from smoker and rest a bit while I let the smoker cool down, then place them back in and hold. I put an extra temp probe inside the smoker with a remote so I know if for some reason the smoker drops below set temp. like if the power should go off or something. I set smoker to hold at 147*-150*. I can tell you this method of holding for 10 or more hours has prodeced some of the best brisket and other meats around, it really renders the fat out without doing it out. A lot of the top smokehouses hold their brisket and porkbutts for 18-24 hrs, most places are a day ahead on their cooks. Even the world famous Katz's restaurant in NY hold their pastrami, they are always a day ahead on their cook, today's cook will be held over night and severed tomorrow.
I find cooking to 180* pulling and let rest and cool a bit while smoker is cooling then holding at least 8 hrs produces the best product, you still have a good bark, great texture and perfect rendering and moist. Oh yea, after resting the wrapped meat wether its wrapped in butcher paper or foil I then wrap in plastic wrap and put bak in the smoker to hold. If holding ribs I will wrap in butcher paper first choice, foil second choice and no plastic wrap on ribs unless you like fall of the bone.
On cooks that im not going to hold over 5-6 hrs, say if I put the cook on late at night and serving the next day, once I wrap at 165* or so I will the program the smoker to cook until 180*-185* and then kick down to hold at 150*, that way I can sleep and not worry about it. I don't wrap in plastic wrap in this case and don't pull to cool or rest before resting in the smoker. This works very well as it carryover cooks a bit while the smoker takes time for the temp to drop.