Google Structured Data (Rich Snippet) warnings/errors when using billboard layout
If you are experiencing any issues with google rich snippet testing tool on billboard non-review (standard article) posts, the issue is because google is looking for an image (i.e. the "article" node is empty). You need to set the featured image to display actually within your content via the post layout options. It isn't enough to have the featured image display as the billboard overlay background, google actually needs to see the image within the post content as an image element rather than a CSS background image.