3051.40000.1349.xxxx and 3051.40000.1351.xxxx its a firmware version (not OS version) and diferent phones (hardwares) have diferent firmware (cause they have diferent hardware. The firmware contained in these phones provides the control program for the device, and is distributed by manufacturers (like Nokia).
The OS version (last version is 8.0.xxx) is distributed by Microsoft. (like Google distributes Android 4.4).
And stop writing a lot of "???" its annoying!