iOS 12.4 (build 16G5056d) is an official Apple over-the-air update for the iPhone 6, released on 2019-06-24T17:17:28Z. The update package is 298.75 MB. This is a delta (partial) update that requires 12.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: e96ff1496454f057edf0773b2213194a6359a89e.zip.