Adaptive forms - prefill attachment

I have a form with multiple attachment components on it.
On draft save the data will be send to an external system. 
Later the form can be continued and is prefilled with the data from the system.
All fields are bound to a xsd scheme. 

What is the support on aem to prefill the previously saved attachments? 
So the user can open the attachments in the browser after opening the prefilled form.

Thanks