My status will be upgrading from Silver to Gold next week. Will existing itinteries automatically show the new status and automatically begin upgrading at my new window?

In the past when I was a medallion on Delta, when your status changed the system did not recognize it for existing reservations and I had to call delta to have my FF # removed and then re-entered into the reservation for the existing reservation to reflect my new status.

Has anyone had any experience with this on US?