iOS 12.3 (build 16F5117h) is an official Apple over-the-air update for the iPhone 6s+, released on 2019-03-27T17:06:27Z. The update package is 329.83 MB. This is a delta (partial) update that requires 12.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: fda205f4f7e70d4c09e2a268d3c5193b96e344ef.zip.