How to retrieve internal interface draft data?

To my knowledge we cannot access any data "saved" in memory with the OOTB save function.  What I typically do here is disable this built-in save function on the User Input task, and create my own "Save For Later" type button within the form layout.  This will bypass validation, and technically submits the form to only chain through a Write to DS node, and chain back to the same form, typically with a custom "Data has been saved" type message, where they can X it closed and re-access from their Tasks List later.  This will persist the current values to the database where we can access them for reporting. 

There are no ways that I know of or have heard about here.  That data is considered to be stored basically as internal "cache" type data in the appian engine, up until the form is submitted.  Many of us prevent the use of this feature and instead implement our own.