First, I need to install interim firmware that is provided by Cudy. They have the file in a public Google drive. I think that this intermediate step is needed because the factory firmware will otherwise block the flash to openwrt. I am clear on this step.
Next, I need to install the latest openwrt version. Here is where I am confused.
there is one column titled, "Firmware Openwrt Install URL" (factory image) and one column titled, "Firmware Openwrt Upgrade URL" (Sysupgrade image)
Which of the 2 downloads should I use to change from the Cudy provided interim firmware to the latest version of openwrt?
It is standard procedure, for FIRST flash of “official” openwrt (onto suppliers openwrt variant) to use the factory image. Afterwards, to use the sysupgrade image. Worked for me for the TR1200 and the TR3000, BTW. Thus, use the “Firmware Openwrt Install URL” on top of intermediary Cudy firmware.
First download and install the intermediate version of OpenWrt provided by Cudy. This version is needed because Cudy firmware only allow to flash signed firmware. Browse 192.168.10.1.
You will enter than enter a classical OpenWrt at 192.168.1.1. Sysupgrade the latest version.