Line Limits (Usage) on a group of line discount modifier

 Hello, I am trying to create a modifer to apply a one time discount ($20 off of order) applied to a group of lines on an order. It works fine until I set a usage limit (1 time), and there are multiple lines on the order. It will only apply the proportional discount on the first line; i.e. the first line consumes the usage limit.

My set up is Level: group of lines, Modifer type: Price Break Header.   However, I have encoutered the same problem with the modifer type as Discount.

Is there a way for the usage limit to apply per order, and not per line?