They won't be dry, but they won't be fall off the bone either. If you want fall off the bone then your going to have to foil for at least 1 hour.
Try Chef Jimmy J's foiling sauce. Here is the recipe:
Foiling Juice
For each Rack of Ribs Combine:
1T Pork Rub, yours
1/2 Stick Butter
1/2C Cane Syrup... Dark Corn Syrup...or Honey
1/4C Apple Cider...or Juice
1T Molasses
Optional: 2T Apple Cider Vinegar. Add 2T Mustard and 1/4C Ketchup to make it more of a KC Glaze.
Simmer until a syrupy consistency.
Allow to cool for 5 minutes, pour over foiled Ribs and
run your 2 hour phase of 3-2-1. For the last phase return
the ribs to the smoker BUT reserve any Juice remaining
in the Foil. Simmer the Juice over med/low heat to reduce to a saucy thickness. Glaze the Ribs for presentation or service.
Al