Standard Checkout for Pre-orders to Apply Discounts

I have an automatic discount set up in Shopify that should apply when customers add 3 items to their cart. However, when a customer placed an order that included a pre-order item through your app, the automatic discount didn't apply. I believe this is because the app is creating draft orders instead of processing through the normal Shopify checkout flow, and Shopify automatic discounts don't apply to draft orders. It would be helpful if there was a setting in the Notify Me! app to ensure pre-orders go through the standard checkout process so my automatic discounts will apply.