Asus released the Zenfone Max Pro M1 about a year ago. The device ran on Android Oreo out of the box and received the update Android Pie about a month ago. Said update was limited to the Indian market, however—which makes sense considering the device was mostly built for that region. The company is now sending out the Pie update to users of the Max Pro M1 across the globe, however.
The update to Android Pie comes with the build number 16.2017.1905.053 and doubles up as the May security patch, which is nice, considering the fact that we're still in May. The download weighs in at a svelte 1.53 GB and brings fixes for a non-functional Call Waiting feature, and the No HD option in PUBG.
Like with most major OS updates, the rollout is gradual and will eventually get to all users of the Zenfone Max Pro M1 over the next few weeks.