iOS 13.3.1 (build 17D5050a) is an official Apple over-the-air update for the iPhone X (GSM), released on 2020-01-22T18:07:23Z. The update package is 196.89 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: 0b3c70938acb9aa15ff053a32044fffe24e7d1e1.zip.