iOS 8.3 (build 12F70) is an official Apple over-the-air update for the iPhone 6+, released on 2015-04-08T17:56:16Z. The update package is 579.65 MB. This is a delta (partial) update that requires 8.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d85c8e4a7746c3b8e4fb94d674b3dd90c31cae0e.zip.