Excluding customers with a specific price level from a shipping strategy


We offer $0 shipping for 12 bottles and this is built into our shipping strategies instead of using a promo. Long story on why. Anyway, I am trying to find a way to exclude the people who receive our employee price level from receiving the free shipping on 12 bottles, and instead receive half off shipping for 12 btls. I have tried creating a flat rate promo to apply just to specific price levels but it seems that the shipping strategy trumps the promo. Any ideas? i am thinking i am out of luck…