Feel free to pull them just shy of done if you can gauge this. If not, don't worry about it but if you're going to grill to reheat (I would too) with a glaze then do one of two things: either pull them when done (or just shy if you can) and allow them to cool--uncovered--for a bit then get them in the fridge to chill, then wrap; transport chilled, then reheat on the grill (glaze after they've heated) or pull when done (or just shy) then wrap individually in foil and stick in cooler for transport and to keep the heat up.
It's true that they can overcook if pulled at done then wrapped for a while. However, either pulling before they're done or minimizing the time between the WSM and the reheat can work too. For this, set up your cook so you can leave shortly after you pull the ribs. Put each slab on its own piece of foil and rest on your kitchen counter for 10-15 min before you leave--foil open and not covering the meat--then wrap to enclose and go. (This will allow much of the heat to dissipate, minimizing the chance of overcooking in the foil.) Just carry the slabs in a bag. Arrive, set up the SJ, heat, glaze, finish; serve. If the time from the point you remove the meat from the WSM to the point when you reheat it on the SJ is less than 2 hours or so, you'll be fine food safety-wise. (For further insurance do not touch the meat with your hands before cooking.)
You can use your rotis for ribs, btw. I agree with Paul and wouldn't for the BRITU recipe/procedure but it works well. My favorite for rotissed ribs: a paste of fresh garlic, fresh parsley, dried herbes de Provence, Dijon and evoo.
Kevin
On edit: fixed typos