Currently, the only way to update the firmware on the LTPP3(G2) is via a USB flash drive or a microSD card. While it's not a particularly difficult process, you will need access to a computer with Internet access and to the device itself, as well as removable media and a USB Type-C cable.
Before you begin
Before conducting a firmware update, you'll need a computer to download the firmware image, which can be found here — sort the directory by Last Modified file to find the latest version. There are three variants for each release: base, free and tiny — the type is appended to the end of each respective ISPBOOOT.BIN package. Base is the standard release, while free excludes Node.js and the Web Interface, and tiny further excludes the SSH server, TZdata, gdbserver, tcf-agent, rootfs autoresizer, and u-boot-fw-utils. Whichever version you download, the file must be renamed to just ISPBOOOT.BIN and copied to either a USB flash drive or a microSD card, which should be formatted as FAT32 with a block size of 2,048.
If the board is installed in a Size 3 Linux Tibbo Project Box, you will need to remove the top cover — and the vibration protection plate, if present — of the enclosure to access the serial-over-USB console port and to jump CN11. While following the progress of the update via the console is technically optional, we strongly recommend that you do so not only to watch for errors, but to verify that the process has been completed.
With the device powered off, insert the USB flash drive into one of the USB Type-A ports or the microSD media into the card slot. Place a jumper on CN11 — perpendicular to the nearest edge. Connect your computer to the console port on the board with the USB Type-C cable; this would also be a good time to start your preferred serial console software (see Serial Console).
When you power on the device, it will boot up, scan for removable media, and begin the update. In the serial console, you'll see various sequential write operations and the saving of the environment to MMC. When the process is done, "ISP all: Done" will be printed on the console. Unplug the power and remove the jumper, the update media, and the USB Type-C cable.
Power on your device and verify that the firmware update was successful. If there are no issues, you close the enclosure and resume normal use.