Once a new version of Pico-UTM firmware is released, Pico-UTM will show a notification in [System] > [Firmware Upgrade] page, as long as the license is valid and the Pico-UTM is connected to Internet. After you pressed [Burn] button, the Pico-UTM will start upgrading.

Note: The Pico-UTM will reboot during the upgrading. The Internet connection will be interrupted and resumed after the reboot.