iOS 12.4 (build 16G5027g) is an official Apple over-the-air update for the iPhone 6, released on 2019-05-15T17:05:44Z. The update package is 208.45 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: c45e226b00a2bf9010b2b9c530e75c14c78616e3.zip.