True, I have given up on some vendors who keep popping boards with revision and no proper documentation. It is a never ending software update process and mostly unhappy users.
They were on the right path until they got android support as tier-1, so now they changed path to uboot 
I moved to x86 and it is running on almost the same wattage like arm sbc. +10-20% is not a lot of difference.
There have been effort from bsd team to get uefi/edk2 for these devices.
Please look at Radxa E23/25 which already have good uefi support. both lan should work.
While R5S/R6S should get supported soon too 
With that working, ipfire aarch64 generic images should just work fine.
@cabletwister
if you have R5S then you can try the R5S Uefi/edk2 image
Flash it on sdcard. Flash Ipfire on usb and boot 
Was looking at some ARM router options and with Rockchip RK356x and RK3588/s we have so many options to choose from.
- NanoPi R5C/R5S/R6S
- Radxa E23/25
- Station P2
Amlogic Option:
- BPI M2S (DT Patch sent upstream for kernel 6.4)
Good luck.