This is a warning to those in large environments who buy the 'lab license'. You buy in packs of 100. If you reinstall or replace a computer mid license term then you cannot reclaim or release the license and so the (same) reinstalled computer uses a NEW license. The license activations are recorded on their website and is based on a 'MachineID' which changes if you reinstall the OS.
To deploy you create a XML answer file. On the command line you add a path e.g.