Well, in the meantime, I found a working image on the OpenWRT forum post that at least boots and has a web UI.

Is anyone else able to get the latest rk3328-sd-friendlywrt-5.10-20210305.img to boot? Or is there a place to download older versions that do boot?

Thanks for keeping us updated igorp!

nothing yet that has wifi ac built in along with 2 gigabit ports that you'd need for normal routing...

any more details about your specific config?

Any progress on flashing custom boot to the SPI which allows network booting?