iOS 12.1 (build 16B92) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-10-30T17:16:24Z. The update package is 1.69 GB. This is a delta (partial) update that requires 10.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 50dbea1aa10e26e7fc5e17ff8bf7f4c57ef655f5.zip.