iOS 9.9.13.1 (build 17A5831c) is an official Apple over-the-air update for the iPhone 8 (Global), released on 2019-09-04T17:06:09Z. The update package is 2.73 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: a77831a563c8b6dc8369ece5f46ad573abf8470a.zip.