The order of these drills is our own design. No source sets a training order.
Each step is taught as a zone in cents, with a badge for its confidence and its source. A zone is what its source reports. It isn’t a target to hit.
Choices in a question are always at least 35¢ apart. That figure is the gap Farhat’s numbers leave between the semitone and the neutral step. It’s this drill’s own rule, not a limit on what anyone hears.