Dozens of Fire tablet owners from across the web, Amazon's support forums, and even the comment section of this blog are reporting that they are turning on their tablets and discovering that the tablet has been wiped clean:
I just LOST EVERYTHING on my Kindle Fire 8.9 (bought two years ago). Nothing on my DEVICE … nothing on the CLOUD. It said I was a new user and sign in. SO I DID … and I have been working for two hours trying to get everything back. But EVERYTHING will have to be RELOADED. And magazines I have SAVED for two years is GONE and it will only show 8 back issues!!!!!!!
The epidemic appears to have broken out on Tuesday of this week, and quickly grew worse on Thursday night as dozens of new cases were reported. Most of the reports which mentioned a tablet seemed to involve the Fire HD 8.9, but there are also a handful of similar reports from Fire HD6 and Fire HD8 owners.
No one knows why this is happening, or whether it is a bug or faulty update, but similar incidents have happened before.
In 2012 a faulty Fire tablet update activated the optional parental controls on some Fire tablets. Dozens of owners reported being locked out of their tablets when it demanded a password which they had never set.
Fortunately the tablet owners had ways to recover access to their account, and so in most cases this was a nuisance rather than a catastrophe, but we're not so lucky today.
Amazon is reportedly aware of the problem and is working on a solution, but there's nothing to be done to recover the content lost from the affected tablets. If it wasn't backed up elsewhere, those impacted by the deluge are simply out of luck.
And with the apps install from the Amazon Appstore, even the standard practice of backing up all content will be no help; Amazon doesn't offer any way to save the settings and app data (this is an option with Google-registered tablets).
Something tells me Amazon will address that issue in the next Fire OS release.