You can do the chill-then-pull-later thing, it's just that you want to cool quickly.
Rest the brisket after cooking but don't bother wrapping it. Toss something lightly over it (like tent with foil) to keep off flying critters. (Separating into large muscles along the natural fat seams will allow for quicker cooling, so consider this. Not crucial but reheating will be quicker as well. If you want to do this, do so after the butt has cooled a while on the counter.)
After 60-90 min fill a tall narrow pot with ice water. Place the butt (or butt sections) into a couple Ziplocs or vac bags then, being careful to keep the bag opening above the surface, plunge the bag(s) into the ice water and allow to sit till chilled, replacing ice as necessary. When chilled well, seal and frisge.