iOS 9.9.13.4 (build 17E5255a) is an official Apple over-the-air update for the iPhone 6s, released on 2020-03-10T17:21:31Z. The update package is 2.71 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: f8d0b647aef1b294bcdecdf7672bebb73bd06598.zip.