Single Phone License means that only one phone can be activated to work fully within our software. After you activate the license it becomes locked to the one specific phone and cannot be changed. Only option of how to activate different phone is to buy another Single Phone License.
You can of course transfer data with Single Phone License, because only the destination device is required to be activated in order to proceed with the transfer. Be careful not to activate the source device as it is not needed and you would have to buy another license in order to transfer data.