iPadOS 9.9.11.1 (build 15B5066f) is an official Apple over-the-air update for the iPad Pro 12.9-inch (WiFi), released on 2017-09-27T16:55:40Z. The update package is 1.75 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: 125c308666f484a87240a33697f3226c5402e6a7.zip.