The standby light should start flashing rapidly, indicating the update has started. You can release the button now.
Updates can sometimes improve Wi-Fi stability, app compatibility (like Netflix or YouTube), and overall system speed. How to Install the Firmware (USB Method)
Understanding the HK.T.RT2861V09 Mainboard and Firmware Updates hk.t.rt2861v09 firmware
HDMI (multiple), USB 2.0/3.0, RJ45 Ethernet, and Wi-Fi. Why Do You Need a Firmware Update?
There are three primary reasons you might be searching for the : The standby light should start flashing rapidly, indicating
If you install firmware intended for a different screen size or panel type, you might end up with an upside-down image, distorted colors, or no display at all (though the TV may still boot).
If you have replaced the LCD panel, you may need specific firmware to match the LVDS/V-by-One signal and resolution of the new screen. How to Install the Firmware (USB Method) Understanding
during this process. Once finished, the TV will usually reboot automatically. Important Risks and Warnings