iOS 9.1 (build 13B143) is an official Apple over-the-air update for the iPhone 6s+, released on 2015-10-21T17:16:06Z. The update package is 313.58 MB. This is a delta (partial) update that requires 9.0.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d553079ce5b293e41b3929024c84ec2fe146b02e.zip.