iOS 13.3.1 (build 17D5044a) is an official Apple over-the-air update for the iPhone X (GSM), released on 2020-01-14T18:21:03Z. The update package is 242.82 MB. This is a delta (partial) update that requires 13.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 3d07111eaf4862fb1e3ec8a09ccb8c12128d43fb.zip.