1Mix white sugar, brown sugar, sea salt, chile powder, garlic powder, onion powder, paprika, ancho chile powder, black pepper, rosemary, thyme, cumin, nutmeg, allspice, and cayenne pepper together in a bowl to make the rib rub.
2Coat ribs evenly with rub. Cover with plastic wrap and let marinate in the refrigerator, 8 hours to overnight.
3Preheat smoker to 300 degrees F (150 degrees C) per manufacturer's instructions. Place ribs on smoker meat-side up. Smoke until browned, about 1 1/2 hour. Remove from smoker.
4Pour apple cider into an aluminum roasting pan. Position ribs in the pan, standing on end if needed. Cover with aluminum foil. Return to the smoker. Continue smoking ribs until tender, about 2 hours more.
5Transfer ribs to a grill. Brush barbeque sauce on top. Grill until dark brown, about 10 minutes per side.