When upgrading to Windchill 12.1.0.0, during data migration, the existing co-produce objects are saved in the /Default/CoProduce folder under the context in which the associated primary part is located. You can change the default location by specifying the required folder path in the following property: com.ptc.windchill.mpml.coproduce.migrate.folderLocation

You can only modify the folder path for the co-produce object but not the context under which it is saved. The property is located at WT_Home/codebase/com/ptc/windchill/mpml/xconfs/mpmlink.wt.properties.xconf.