HMD Global has started to push new software update for Nokia 7 Plus and Nokia 6.1 / 6 (2018) Android One Editions. This update is now available in India and brings Android 8.1 Oreo upgrade, Dual VoLTE support and May 2018 security patch for both smartphones. The roll out has already started and some users have shared the installed screenshot on third party forums.
According to the source, the software version for both Nokia 7 Plus and 6 (2018) will come as V2.22A, which means both are getting the same version. The firmware update will also done enhancements in user interface and tweaks the system stability. The download size of this oreo 8.1 for Nokia 7 Plus will be in 441.7 MB and for Nokia 6 (2018) the update weighs in 460.4 MB. Both handsets will receive this update as OTA and requires WiFi connection for download.
If you own any of these two handsets, you will receive the automatic OTA prompt. The OTA phase roll out will take more time to reach all handsets, so be calm and wait for the notification. Also you can check for the update manually from Settings menu, to know whether the update is available or not.