iPadOS 11.2.1 (build 15C153) is an official Apple over-the-air update for the iPad mini 4 (WiFi), released on 2017-12-13T18:07:21Z. The update package is 527.08 MB. This is a delta (partial) update that requires 11.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c559ba4e64f4471e135739af76ec1b5e07d85379.zip.