Followup: The factory image is now available for download.
This will however require a factory reset of the device.
The Android 7.0 Nougat release is now finding it’s way (slowly) to Nexus handsets. If you’re one of the impatient ones (like me) you can force the OTA update with a few simple clicks.
This is confirmed to work on the Nexus 6P.
- Visit https://www.google.com/android/beta?u=0
- Login with your Google account
- Enroll your device into the Google developer build programme
- You will receive an OTA update shortly. If you don’t want to wait you can force a refresh by visiting: Settings > About phone > System Update > Check for update
- Once the update has installed be sure to “Unenroll” your Nexus 6P from the developer programme by visiting the site in step 1
On the Nexus 6P the build number will be NRD90M
Source: Comment by “thacounty” on http://goo.gl/sMWpcZ