Got this email from Dynadot today:

We will be adding a new account security feature called the access level lock to help prevent anyone from unlocking your domains or changing your account information without your permission. A user must authenticate himself before he can make any of the aforementioned changes. The access level lock will automatically re-lock itself after one hour has passed.

This change will become active within the next week. If you need to edit your account information, please do so now. If you have any questions or concerns, please let us know.

Best Regards,
Dynadot Staff