The DHF is a living document.
Logically to me it doesn’t even make sense why it wouldn’t be. What is the point of documenting just the original process if you are going to open a 2nd DHF if the product changes due to indications of use or design changes? The DHF should be the original changes plus the ongoing continuous changes of that product.

At the company I currently work at, we made a minor change to the material of the fabrication of the device and every step of the process was recorded and documented under the current DHF that the device was created under. I believe opening a second DHF, which may have a lot of the same information as the current DHF of the product, would be a waste of time and resources.