Q: I am unable to update to the latest build
A: First, make sure your device is still on the Preview for Developer program. If you had hard reset your device since installing 12359 you may to reinstall the “Preview for Developers” app and set it up again to take the next update.
To make sure you are enrolled in the program, go to the Preview for Developers app, sign in (if necessary), and check the box next to “Enable Preview for Developers”.
Note: If your device is enabled for the update but no new version is made available to you: There are a small set of devices for which we aren’t offering the latest build of the Developer Preview program due to an identified problem that requires mobile operator or OEM driver updates. These will be offered when the official update for your phone is available.