There is no guarantee of what version will be on the devices when received from the factory, and it also could depend on which device. It’s currently 1.4.4 on all devices except the tracker, however.
We recommend flashing Device OS, bootloader, Soft Device (Gen 3) and user firmware to the device to make sure it has the version you intended to have on it. This is typically done by JTAG or USB. It could also be done OTA.
Flashing all four using a Segger J/Link using SWD/JTAG to a Gen 3 devices takes less than 10 seconds.