iOS 9.1 (build 13B5139) is an official Apple over-the-air update for the iPhone 6s+, released on 2015-10-12T16:57:00Z. The update package is 1.64 GB. This is a full OTA update that can be applied from any compatible base version. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 20ac1e536f6fc3ba70ad4562e56296e1502d349b.zip.