How to use the Content Delivery API to retrieve multiple stories, including those that are both not published and on a release?

For example, my Content Delivery API request looks something like:

I the request, I’m trying to get all stories whose path starts with “foo”, including those from the release “5678”.

It seems that the Content Delivery API response will only include stories from the “5678” release if they are published on the “Current” release.

But, I do not want to publish those stories until the release goes live (ex = the “Release Now” button is clicked). They are not supposed to be available to our visitors until the release goes live.

How can I get those unpublished stories into the (draft) API response (so that I can test in my dev environment)? It seems like they should be in there already since I’m using “&version=draft”?