Regardless what everyone else has said, when I was on Zoom waiting to get a firm date to head to OKC, we had a guy switch from terminal to en route. We asked how and why. He said the list of places he could end up with en route was better, and he simply called and asked, and had it granted.
At the time we were also getting the first 13 non-radar lessons on repeat, and he joined us with about a week to go.