For the update procedure it is highly recommended to unplug all servos as the servo can go to full deflection during the setup. This is because the outputs of your device will not send out any signals during the update process. In such situation some servos can behave very strange or unforeseen, especially cheap servos with bad servo software. Using an electric heli it is also recommended to unplug the motor from the ESC or unplug the ESC or main battery in case this is not used for powering the radio system (no BEC), so the motor will not start by accident during or after the firmware update.
