I'm far from an expert but I usually pull my picnics at just over 200*. You should be in for some good eats with that,picnics always taste good. I don't do as many as I used to because, even though they're cheap, there's so much waste I'm probably better off buying butts. You should be in good shape, once you're over 190ish you could probably glaze and be set no matter what. Tough to screw up a shoulder. Some will be better than others but they'll all be good. I have had some very, verrrry, long smokes on picnics before. Record was close to 19 hours but it was still delicious.