Yesterday I was setting up a new release on KDP. Everything went well until after the final click. I got the usual message about it taking up to seventy-two hours to be available in the Kindle store. However, when I returned to the main bookshelf page, the book was labeled "draft," and the button said "continue setup." Clicking the button just pushed me back to main bookshelf page again. It looked as if the process jammed, and there was no way to unjam it on my end.
I tried all the usual things: clearing the cache, restarting the browser, trying a different browser, restarting the whole computer. Nothing worked.
I wrote to KDP support right away and explained the problem.
When I got up this morning, the book was live, and the product page was complete--the Look Inside is already up. Either it was only the bookshelf that was out of whack, and the book was actually publishing in the background, or customer service fixed the problem really fast.
Just to be on the safe side, I think it's a good idea to shoot a message to customer service right away. Sometimes that won't produce results, but the rapidity with which the problem was corrected makes me think it did this time. (That's the fastest the Look Inside has been up in a long time, at least for me!)