iOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPhone 6+, released on 2019-01-22T18:10:09Z. The update package is 1.39 GB. This is a delta (partial) update that requires 11.2.5 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c136ff0fe53157a5c6e1bf40b3cfab5a4f18d396.zip.