If you have an Amazon Kindle, pay attention... An update is required BEFORE 22 March 2016.
This page on Amazon Kindle Updates lists versions and instructions on how to update.
Amazing to me I didn't get an email from them about it.
Interesting; presumably they've got a built-in digital certificate that's expiring.
Toastiewarm: Yup even more helpful when you do what they say to update and they can't give the update, guess I'll have to manually update
4-5 days late I guess