Debian doesn't directly support rk3399-nanopc-t4,dtb, u-boot does but not the kernel.
there's all sorts of issues with 5.x.x kernel rk3399-xxx.dtbs
OpenBSD uses dtb from 5.x.x linux kernel which is variously broken - usb3, hdmi, ......
Friendlyarm 4.4.x kernel has good support
Armbian 4.4.x seems to have the best of all worlds, and now I've found is simple to implement sysvinit
I'm now running far less daemons and background apps for a more targeted system.
bigtreeman got a reaction from Werner in Replace systemd with sysvinit