iOS 12.0 (build 16A5362a) is an official Apple over-the-air update for the iPhone 6, released on 2018-08-20T17:05:27Z. The update package is 1.21 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: c33d765897f5d0c21c6921978db0b1b68da09c67.zip.