Nokia Mobile has started the rollout of the January update to the Nokia 7 Plus as well as the Nokia 6.1. The update brings nothing else besides the Android security patch for January 2019.
The update weighs 94.9MB in case of 7 Plus and 103.4MB for the Nokia 6.1 (via NokiaMob). It appears to be available across multiple regions since users from manu areas have reported receiving the updates. Your device should notify you automatically about a software update, but you can also invoke a manual check by heading to the device’s settings.
Based on some internal leaked releases, a maintenance release for the device is also ready, fixing some issues. It can get pushed this month itself, else clubbed with the February security patch update.