How to generate Facebook preview on Scheduled WP posts?

Hypothetical: I have a post scheduled to run on my WP site an hour from now. I want to go to my Facebook page and schedule a status update to run an hour and ten minutes from now, with the bit.ly link in it and the preview image / excerpt, running the same way it would if I was linking to a page that had already been published.

FB won’t find the image or the excerpt until the page has gone live, but it tries to generate those elements as I’m writing the status update.

Is there a workaround? I looked at the Publish Post Preview, but that wouldn’t allow me to make use of the bit.ly URL.