As-Of versions can not saved directly because they are intended for temporary analysis.
Indirectly, however, in the DRM interface, copy the As-Of version with a new name and the newly created copy can be saved.
Via the batch client :
Use the batch client to export an as of version to file.
Please see https://docs.oracle.com/cd/E40248_01/epm.1112/drm_user_11123500/frameset.htm?ch16.html for the parameters that can be used in the Export Section of Configuration File