My N6 is on Nougat 7.1.1 January security update which I flashed manually. I haven't seen the March update OTA and I wonder if I will ever get it having flashed the 7.1.1 manually.
I was thinking of flashing the March update manually using the instructions here
https://developers.google.com/android/ota
I am guessing that if all goes well I won't have to restore any data since I am sure that's what I did for the original Nougat release but just checking.
The phone is backed up but it's a pain to have to remember all the logon passwords etc. for 3rd party apps which Google doesn't seem to save in its backup.
Reason for update - the speakerphone bug is really annoying.
