Good questions! I actually had to google for the answers. Yes to your first question, you still get the same benefits as if you were eating it unground. As for your second question, there weren't any concrete answers so that is up to you. If there were buttermilk in it, I would say yes it'd still be good because it is a natural preservative.
Your pancake mix would probably settle after sitting in the fridge for 24 hours and you would need to mixed again before cooking, but it would still be good.
Don't forget you can freeze cooked pancakes and warm them up the next day...or week....or month.
Oatmeal pancakes!!!!
