A new OTA update has landed on the Xperia Z2 (D6503) in some regions, moving the build version from 17.1.A.2.55 to 17.1.A.2.69. Some users claim that this is the version that their Xperia Z2 had shipped with. Overall, it looks like a minor update over the previous version, which most likely quashes bugs and enhances performance.
Via XDA-developers.