I have maybe a stupid question, but I would like to know
is "A64-OLinuXino" compatible with operating systems that are made for: "Aarch64" ?
Because I found this nice (and secure) mini operating system that I would like to
test: https://easyos.org/
http://distro.ibiblio.org/easyos/aarch64/releases/pyro/1.0.4/
https://linux-sunxi.org/A64
So "all" you need to do is to re-write all the low level code to drive hardware devices (clocks, peripherals, etc).
That will include workarounds for silicon bugs such as the time (wall clock) one(s).
John