Anytone AT-D578UV Pro Tx extended. All you need to do is to press the channel knob and the P4 button at the same time and turn on the radio. Once rebooted you then have a choice of which band you want to use by turning the channel selector to the appropriate band, then reboot your radio.
PLEASE NOTE that all the previous settings etc.will be lost. And you my have to reinstall all your setting again.