How to direct Hummingbird to include combined CSS files in footer?

I am using hummingbird on a website to improve the Google PageSpeed score. It's helping quite a bit, and has brought my scores up to 84 for Mobile and 94 for desktop, however I cannot seem to get it to allow me to move the combined CSS files to the footer. There are only three files left that are getting flagged for blocking, and they are the main, custom, and media CSS files created by Hummingbird.

What do I need to do to direct these files into the footer?