Looking for USB Upgrade Tool for VIM3L

I have a project previous running on Edge V but I want to try using VIM3L instead.

There is a part where in Edge V there is this upgrade tool for Rockchip in Khadas Edge V. Can the Khadas Team please advise on something similar that can be done on VIM3L which uses Amlogic? Unfortunately, I cannot attached the document in pdf what was done for Khadas Edge V. Also a document (in Chinese) from Rockchip.

Check here:

https://docs.khadas.com/linux/vim3/InstallOsIntoEmmc.html

@numbqq Thanks for the information. I see that the update.img in my Khadas Edge V actually prepares the board with Ubuntu Desktop 18.04.1 LTS. Is there any Ubuntu Desktop 18.04.1 LTS image for VIM3L?