In Dynamics 365 Portals, Webform steps have fixed modes(Insert, edit and Read-only). often we need the forms to do things differently. Allow users to create and submit details. Allow users to edit the submitted details and present submitted details as read-only.
As such we often end up creating multiple copies of the webform each catering to different mode scenario. One for creating new submissions, one for edit an existing submission and one to check the details of submission in read-only mode.
My suggestion is to allow Webform step mode to be based on criteria(Ideally Status Reason).