iPadOS 9.1 (build 13B5143) is an official Apple over-the-air update for the iPad Pro 12.9-inch (Cellular), released on 2015-10-21T17:15:46Z. The update package is 1.5 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: 1bbfadf04950a7acec7377e88789d0d62ccf3fe3.zip.