EEDI2().TurnRight().EEDI2().TurnLeft()
Which doubles the height, rotates the image 90 degrees, doubles the height (width) again, then turns the image back. Since the jaggies are horizontal-only for the reasons you described, I think you only need to:
EEDI2
Which doubles the height, rotates the image 90 degrees, doubles the height (width) again, then turns the image back. Since the jaggies are horizontal-only for the reasons you described, I think you only need to:
EEDI2
and then scale vertically to 66.6...% and addborders/crop (depending on whether you crop initially or not) as necessary to get back to 480 pixels.
DE