According to the official rules as posted at The World According to Nick:
The Carnival will be posted at the host site every Thursday, and submissions are due Wednesday, preferably before 7 PM Central Time. This is to allow the host to have plenty of time to put everything together, as it is a lot of work. If you're late submitting, its purely at the discretion of the host whether to include you or not.If you'd like to submit a post from the past week (or further back if its still relevant), there are many ways you can do it:
Send an email directly to badgercarnival@gmail.com. Please be sure to include the direct link to your post, as well as the name of your blog, and a short summary of your post to help the carnival host.
Use the Blog Carnival Submission Form. You can also view a list of all previous editions of the Carnival of the Badger at the Blog Carnival Archive Page.
Use the Carnival Submit Form from Conservative Cat.