I have an Apple ID that I use for both the App/iTunes Stores and for iCloud. Because I originally created it years ago, it's an email address I no longer use, let's call it
firstname.lastname@example.org. I would like to replace it with
This is easy enough to do from the Manage My Apple ID web interface, however when I change the address and attempt to update my iPhone and iPad I hit a snag: in order to Sign Out of my Apple ID in iCloud Settings, I must first provide my Find My iDevice credentials, since that prevents a thief from simply punting me out of my device were they to steal it.
The problem is, it asks for the Apple ID password for
email@example.com, and when I enter that, it fails (with the incredibly helpful message "there was a server error"). I have to assume this failure is because that combination of email address and password is no longer part of my Apple ID.
Can someone provide me with a sane, step-by-step way to change my primary Apple ID email address from one email that I control to another, given the use of iCloud and Find My iDevice on multiple devices?