The experiment window in Simulation Studio can be saved as a SAS data set. Once you save the experiment window contents, you can edit that data set using SAS and then read it back into your simulation project by right-clicking on the experiment window and selecting the Load Design option. It is important to note that the original SAS data set must be created by right-clicking in the Sim Studio experiment window and selecting the Save Design option. (If you try to load a SAS data set that was not first created from a Sim Studio experiment window, then you will get an error because SIm Studio does not know which columns are factors, responses, etc.)
Once you save your project with the updated experiment file loaded, then you can run in batch mode.
So this approach is not completely automatable since you have to load the new experiment file using the GUI.
Are you looking for a completely automatable approach, or will this work for you?