iPadOS 11.2.1 (build 15C153) is an official Apple over-the-air update for the iPad 5 (Cellular), released on 2017-12-13T18:08:50Z. The update package is 1.02 GB. This is a delta (partial) update that requires 10.3.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 7ec6381d78b2a6bf64d51859ddec186a9333c98f.zip.