Preheat oven to 375 degrees F. Line a large baking sheet with parchment paper.
In a large mixing bowl, combine flour, oats, sugar, baking powder, baking soda and salt.
Using 2 knives, cut in the butter or margarine until combined and it looks like coarse crumbs.
Add in the orange zest, cranberries and add sour or butter milk. Stir until completely combined.
Lightly flour your surface and place the dough on the surface. Using your hands, form the dough together but don't knead it. Form the mixture so the whole mixture is about 1 inch (2.5 cm) thick. Divide into 3 pieces.
Cut 4 scones out of the 3 pieces. Transfer each scone to the prepared baking sheet. Brush tops with milk (not the sour milk!)
Bake in oven for ~25 minutes or until lightly browned on top. Let cool.