Grind 1.5 cup of old fashioned oats
In a large bowl combined both: old fashioned oats and oat flour
Add remaining dry ingredients: baking soda, baking powder, cinnamon, salt and sugars. Mix it well
Cut cold butter into small pieces, add to dry ingredients and using a fork or dough blender mix it in until the dough becomes a bit crumbly. Do not over mix.
Work the butter in fast so it doesn't become warm. If there are still little pieces of butter visible that is ok
Add buttermilk gradually. Do not add all at once. The dough will be sticky but you do not want it to become runny.
Add blueberries and fold them in
Put the dough into a flat surface and form a circle
Divide into 8 somewhat even pieces
Put the scones on baking sheet lined with parchment paper or silicon mat
Brush with heavy whipping cream
Bake at 375F for 18 minutes