iOS 9.1 (build 13B143) is an official Apple over-the-air update for the iPhone 6+, released on 2015-10-21T17:16:04Z. The update package is 308.02 MB. This is a delta (partial) update that requires 9.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c39fb3a7fc53f2d4d2df4beb3f03a7f3c3b661d2.zip.