Ah, the dreaded stall has joined the party after all...
I didn't say anything about it earlier...didn't want to hit you with any bad news..it happens, and you want it to happen for the best end results. Your pork is getting really happy right now...the interior has just become a melting pot for all the nasties...
This is what it's all about my friend, so hang in there. The moment of truth has arrived, so just go with the flow and don't second guess your temps...I still make that mistake now and then...trust your probes, unless something really funky happens...oh, I have seen temp drops of several degrees, especially if I have had temp swings with the smoker, so expect that...it'll come back though...patience, patience, and more patience.
I'll be hangin' with ya for a little while yet, but my bed sheets are calling for work in the AM...almost 11:15 PM here now.
Man, I forgot that you're in PA...gonna be a late one for ya...hang tough, and keep busy here on the forums, or anything else that will help you to pass the time easier...you'll come out smellin' like Bbq!
Have a few all-nighters under my belt myself, and each one gets easier, to the point where (crazy as it sounds) I actually look forward to them now. I get a huge feeling of satisfaction from these smokes...pumps me up like a helium balloon for about a week! LOL!!!!!!!!
EDIT: on temp probes, be sure they aren't too close to a bone, or they can read a lot colder than actual temp.