iOS 9.9.15.2 (build 19C56) is an official Apple over-the-air update for the iPhone 6s, released on 2021-12-13T18:27:55Z. The update package is 3.91 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: 95870e5b57523544b67fa0b24f24b8bff7d1620f.zip.