iOS 12.4 (build 16G5069a) is an official Apple over-the-air update for the iPhone 6s, released on 2019-07-09T17:16:27Z. The update package is 295.33 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: 14180c9b4e206532ce7d1325f0e83bc70d62bcfd.zip.