iPadOS 9.2.1 (build 13D14) is an official Apple over-the-air update for the iPad Pro 12.9-inch (Cellular), released on 2016-01-04T17:58:49Z. The update package is 38.4 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: 28936baad7fcb3c1b5eed5d802d16912e2d37bb9.zip.