To prepare sauce, combine the first 5 ingredients in a small bowl. Cover and chill.
To prepare pork, cut pork in half lengthwise; cut crosswise into 2 1/2-inch pieces.
Combine apple cider vinegar and next 7 ingredients (through garlic powder) in a medium saucepan; bring to a boil. Add pork to pan. Cover, reduce heat, and simmer 1 hour or until tender. Remove pork from cooking liquid; shred with 2 forks. Place pork in a serving dish; pour cooking liquid over pork.
Preheat oven to 425°.
To prepare biscuits, lightly spoon flour into dry measuring cups; level with a knife. Combine flour, baking powder, 1 teaspoon salt, and cinnamon in a large bowl; stir with a whisk. Combine potato, 2 tablespoons sugar, butter, and milk; stir well. Pour over dry ingredients; stir until a soft dough forms (dough will feel sticky). Turn dough out onto a floured surface; knead lightly 5 to 6 times. Roll dough into a 10-inch circle; cut 24 biscuits with a floured 2-inch biscuit cutter. Place on a baking sheet coated with cooking spray. (Reroll dough scraps, if necessary.) Bake at 425° for 12 minutes or until lightly browned. Remove biscuits from pan; cool on a wire rack. Serve with pork and sauce.
Alabama barbecue is known for its vinegary white sauce. To prepare it in advance, combine the sauce ingredients, refrigerate, and bring to room temperature before serving. As for the pork, cook and refrigerate it in the braising liquid, and gently reheat it all on the stovetop before setting it on the buffet. The biscuits are best baked shortly before guests arrive. If time is tight, serve the sauce and pork with small silver-dollar rolls from the bakery.