iOS 9.9.15.4.1 (build 19E258) is an official Apple over-the-air update for the iPhone 6s, released on 2022-03-31T17:14:57Z. The update package is 3.8 GB. This is a full OTA update that can be applied from any compatible base version. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d9c64a3417b921a27c9e21e3a0c7b77b37c34d06.zip.