5.30 may have been impacted by a u-boot issue. I have attempted to use 5.31 image on a Lamobo R1, and the ethernet device would detect, but not send traffic. To test it, I downloaded the 5.25 image and ethernet worked perfectly immediately. To determine if u-boot or something else was the problem, I proceeded to upgrade a single package at a time to determine which was stopping the ethernet from working. I start by upgrading linux-image-next-sunxi and reboot. Upon reboot, the ethernet device stopped working exactly as it did with the 5.31 image.
I'm currently in the process of downgrading the kernel on a 5.31 image to determine if it fixes the issue. But that is taking a very long time. I only seem to be able to get between 300 bytes and 3 Kilobytes per second from the apt.armbian.com server. So I'll post in a couple of hours with my results. If you would like an specific details about my setup, please let me know. I'm relatively new to using armbian and any commands that might be required to get specific data. However I am experienced in Linux.