iOS 12.4 (build 16G5038d) is an official Apple over-the-air update for the iPhone 6s, released on 2019-05-28T17:07:47Z. The update package is 201.98 MB. This is a delta (partial) update that requires 12.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a83ea0b2533f964018460bdf831a42ca043b83ee.zip.