iPadOS 9.2.1 (build 13D15) is an official Apple over-the-air update for the iPad Pro 12.9-inch (Cellular), released on 2016-01-19T17:59:40Z. The update package is 38.39 MB. This is a delta (partial) update that requires 9.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 35179884615b30d0d65c622aae616bd86f35e750.zip.