iPadOS 11.1.2 (build 15B202) is an official Apple over-the-air update for the iPad Air (WiFi), released on 2017-11-16T21:14:28Z. The update package is 1.05 GB. This is a delta (partial) update that requires 10.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ad09193e2cedff7dcaafa86e1e3d3fa3acc7bbe8.zip.