I have worked out how to change a Mac computer name in the JSS console then propagate it out to the client. I noticed that in the example of a name like 'test-name-air', the ComputerName and LocalHostName take this change but the HostName gets truncated to just 'testname'.
I am not sure if Active directory will care about the HostName being different or not. At this stage it doesn't appear to and I would prefer not to have to deal with further complications of scripting the rename of HostName if I don't have to.
Thanks for any help.