Ariel Flashing the firmware on the Japanese version is not possible. The European version seems to be able to flash, but since the prices for the European and US versions are the same, and the bandwidth is also the same, flashing the firmware doesn't seem meaningful. Expanding the bandwidth on the Japanese version is more complicated. See a post on Reddit, where expanding the bandwidth allows you to unlock HF close to the entire band, but unlike the US and European versions, it cannot unlock the aviation band and 440-450 MHz. This isn't very useful.