The in-built post scheduling feature of WordPress is super-handy….until it starts not to work. Then it is a cause of huge headaches. I’ve yet to find a clear cut answer as to why it happens, but sometimes WordPress will fail to publish a scheduled post.
However, the fix is fortunately simple. There is a plugin called WP Missed Schedule. There are no settings – just install and activate. Its sole purpose in life is to check your site every few minutes and if it sees any scheduled posts were missed by WordPress, it will publish them for you. And that is all :)
Link: WP Missed Schedule
image courtesy: http://www.flickr.com/photos/55432818@N02/5500963965/