Right, but to be clear, I had no issues at all renewing my ebooks. They renewed just fine in the Libby app, and I confirmed on the website. But what happened was then, a couple days later, the books on my device seemed to think they had expired (the original checkout period), and were no longer accessible. So then I just manually deleted them, then had to go manually click on each of the already renewed books in the library, and resend them to my Kindle.

So it all worked, manually. I just thought it was odd that when you renew an ebook, the library software wasn't smart enough to communicate with the files on your Kindle device and update the checkout token, so you wouldn't have to manually delete, then re-download, the books you renewed. Again not a big deal, I will probably just ping the library about it and give feedback on their software and renewal process. But wondered if anyone else had seen this or discovered a slicker/quicker way to renew without having to re-download.