Finally the waiting is over. Sony Mobile has started to re-roll the Android Nougat firmware update with the build number 32.3.A.0.376 for Xperia Z5, Xperia Z5 Compact, Xperia Z5 Premium, Xperia Z3 Plus and Xperia Z4 Tablet. Weeks ago Sony Mobile released a firmware 32.3.A.0.372 which is also Nougat for these devices. But unfortunately Sony recognized some heavy bugs on the firmware such as the audio playback and SD card encrypting bugs. So they rolled back the update. Hopefully this new build has fixes for all the defects of the previous build.
Update is available for many regions of all the variants. Wait for some time and you'll receive it shortly. If you've received it share your impressions with us.