Changing Delegators

Hi

Currently, we are choosing to delegate contracts to people acting on behalf of someone else (there are many reasons for this that I won't go into here, but delegating is the only thing that works for us).  Some delegtors (outside of our company) have struggled using the Adobe system and often, we have had to re-start a workflow from scratch and delegate a document to someone else. I know you can add / replace email addresses for "signers", but can such a thing be done for delegators so we don't have to cancel workflows and start again?

Thanks.