Images work in editor but 404 on site

I have recently setup NetlifyCMS with my gatsby site recently for blog posts.

In my config.yml I have:

media_folder: static/images/blog
public_folder: /img

As well as my Gatsby config including:

  resolve: `gatsby-source-filesystem`,
  options: {
    path: `${__dirname}/static/images/blog`,
    name: `blogimages`,

Added an image to the ‘Media’ option in admin (also shows on GitHub), and then added it into a blog post which displays fine in the editor.
However when I ‘View Preview’ the image is a 404.
The default route is within the /static/ folder is where my favicons are located and they load fine, so the issue seems to be only when I use the NetlifyCMS admin to add images to my post.
I have also tried publishing the post to see if it was just a preview issue, but unfortunately the image still leads to a 404 despite it being visible within the editor, media and github.

Any ideas what could cause this?

If your media folder is static/images/blog, shouldn’t your public folder be /images/blog?