In my opinion, the first thought where the DHF is sealed and any updates after the design transfer are added to the DMR seems more logical. Technically, DHF is put together initially when the product was being planned, researched and prototyping it. Once the design is transferred, then any change needed to the product goes through a process and hence it should be recorded in the DMR. The change process evaluates the what it is that is being affected and the risks involved with it. Since, the DMR is an extension to the DHF it makes the DMR more of a living document. The DHF should remain a record of the initial thought process and the DMR can be used for ongoing changes.