Before you start, place butter in the freezer for at least one hour, or until frozen solid. Add flour, sugar, baking powder, cinnamon, and lemon zest into a large bowl, mix to combine.
Using a cheese grater, grate frozen butter into the dry ingredients. Use a pastry cutter or a fork to work the butter into the dry ingredients until crumbly. Stir blueberries/huckleberries and cubed cream cheese into dry ingredients.
In small bowl, whisk ½ cup buttermilk, limoncello, and egg together. Make a well in the center of the dry ingredients, then pour wet ingredients into the center.
Using a fork, gently work the wet ingredients into the flour mixture until the dough comes together. If necessary, add 1 tablespoon of buttermilk at a time to bind the dough together. The dough will be pretty crumbly. Do not overmix.
Cover the workspace with a light sprinkle of flour, then turn the dough out onto the work surface. Gently press and push the dough into an 8" disc.
Using a pastry cutter, divide the dough into 8 equal portions. Slice the dough in ½, then ¼, then ⅛. Do this by lowering the pastry cutter down to make the slices, then slide it outwards instead of lifting it up.
Gently transfer the blueberry scones onto a parchment paper-covered baking sheet and chill in the refrigerator for 15 minutes. This helps the scones from spreading too much. While the scones are chilling, preheat the oven to 400℉. Cook scones for 18 to 20 minutes, or until golden brown. Place scones on a rack until completely cool.