iOS 11.2.6 (build 15D100) is an official Apple over-the-air update for the iPhone 6s+, released on 2018-02-19T21:14:35Z. The update package is 1.25 GB. This is a delta (partial) update that requires 10.3.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: e16b64947cdb387a774c8b7f1b5c1f43ce41ffee.zip.