iOS 13.3 (build 17C5053a) is an official Apple over-the-air update for the iPhone 6s, released on 2019-12-05T21:11:34Z. The update package is 333.45 MB. This is a delta (partial) update that requires 13.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: e06a4546f721d27359592b42f6843b2f95a278aa.zip.