Backstage is good at letting developers request the provisioning of new things (environments, services etc...). However it is not easy in Backstage to model the use case of coming back to the thing that was requested and amend it. The request is to support for  this capability for their environment provisioning use case.
More specifically, a developer should be able to go to something they have already provisioned and be able request to modify it. The same form that was used at creation time should open, but this time it should be pre-populated with the choices made at creation time.
If it helps the design of this feature, we can assume that all the data collected from the form is in a single file in a well-know location (which could be an annotation from the entity representing the provisioned thing).