Until,Smokin' gets a chance to check back in.We visited a forum member's restaurant up in SC.Sort of a Dairy Bar kinda place.
Same situation as yours.They smoked the butt to be ready to serve some on their busiest day.The weigh out pulled chunks for the size servings they needed and stored them in coffee cups with lids in a dedicated refrigerator..They would microwave on the reheat setting,chop slightly and refresh with Smokin's vinegar sauce.
After a couple days ,if they had leftovers,they made the decision to freeze the portions and refresh each day as needed.Their other option for cooler days was to make Brunswick Stew and cook a fresh butt,or use up the last of the leftovers as "special dinners".
Hopes this helps a little.