Has anyone installed Trisquel on RockPi4? | single board computers

I found https://thinkpenguin.com/gnu-linux/how-build-trisquel-11-scratch-tpe-r1500-mail-server and https://thinkpenguin.com/gnu-linux/how-build-trisquel-11-image-scratch-tpe-r1500-easier-way that explain how to make a Trisquel 11 microSD card image for a Thinkpenguin product that is not being sold currently. Perhaps it is because the product is not ready yet.

The hardware seems to be the nanopi R4S. I used the "easy way" to make such a microSD card image and I can confirm that it boots successfully on a nanopi R4S. My motivation for getting a nanopi R4S was to install libreCMC, not Trisquel, so I have not used it much. However, when I did an "apt upgrade" and the kernel was upgraded, there was an error due to "Nanopi R4S" not being recognized by flash-kernel (or something like that, citing from memory now), so that I am not sure the system is still functional. So there might be some issues to fix.

I know that, unlike the nanopi R4S, the rockpro64 has official support from Debian, so it should not have such a problem. I had the idea to try the method described in https://trisquel.info/en/wiki/arm64-chromebooks-trisquel-installation i.e., install Trisquel from Debian. I started but I remember that at some point, u-boot said it could not find a btrfs file system, while I did not understand why it was so because the Debian install only used ext4. I can't remember the details now, unfortunately I did not write down anything, so I will have to retry and see.