iOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPhone 8 Plus (GSM), released on 2019-01-22T18:09:12Z. The update package is 1.51 GB. This is a delta (partial) update that requires 11.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 8d719a712d6c8345fc2369c962034cd0cdf0af6e.zip.