Chinese manufacturer Lenovo has been started rolling out the Google’s latest OS update to their mid-ranger smartphone which has been launched by the end of last year. The company has officially declared the Android 6.0 Marshmallow update notification on their official forums website.
According to Lenovo
we expect Marshmallow to be rolling out for the Vibe P1, P1A42, over the next few days. Please remember to back up all necessary contacts and files before clearing your cache and updating your device. It is also recommended to factory reset your device after updating.
When you have updated, if you would like to report something which you consider to not be working as designed please remember that threads with discussion on multiple issues usually result in nothing becoming solved
The comments followed on the post suggests that the update had already gone live in for Indian users. If your Vibe P1 has not got the update, wait patiently, the update through OTA has just begun and you will get it soon.