How do I change the submitted by field, rendered by display suite?

I'd like to change the submitted by field, rendered by display suite, so that it says: "Submitted on date - time" instead of "Submitted by username on date - time".

Is it possible to override the function ds_render_submitted_by($field) found in ds.module? I tried copying this function to my custom module and changing it's name to module_name_render_submitted_by($field) but this didn't do much for me.

Thanks for any help you can provide.