iOS 12.0 (build 16A5357b) is an official Apple over-the-air update for the iPhone 6s+, released on 2018-08-15T17:07:03Z. The update package is 1.26 GB. This is a delta (partial) update that requires 11.4.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 26c0f2a21a457d3d5ac43783609f19675c1f4045.zip.