hi there,
I’ve got a dual-booted Arch systems
Two copies of ArchLinux with a shared home drive on the same physical drive and PC
in fact they are identical execept for the AMDGPU dirvers differ and host name.
is there a way to stop the registration expiring, when I boot into the other Arch?
many thanks in advance 
License is tied to machine hostname and dbus machine-id, so as long as those don’t change the license willl stay valid.
However whether you can use single license this way or you need to buy a second one – that’s a question for @gchen
License is only tied to the hostname. So if you can boot in to the same host name one license should work.