Admittedly, pork butts are not my expertise but have a quick question...
I was supposed to throw this on last night for tonights dinner, so the rub is on sitting in the fridge. Due to unforeseen circumstances, I'll be unable to smoke the butt until Thursday/Friday. Any harm in letting it sit in the fridge with the rub on for a total of 4 days? I suspecting not, but thought I would ask (though there isn't much I can do about it at this point).
It should be fine.
As long as you weren't bumping up against the "use-by" date.
I have had to postpone smokes before with no issues smoking later.
If you rub is high in salt the butt may put off some moisture.
I agree with FLBR. Make sure it's tightly wrapped and put it in the coldest part of the fridge.
If there's room in the freezer, I might put it in there for 2-3 hours to chill it down and then go back to the fridge. Just don't forget about it in there. :-[
Thanks. Didn't think it would do no harm, but I don't smoke pork butts very often (maybe 3-4 times in last 10 years).
It should be fine just keep it below 40degrees.