Alpha Wolf, you are correct in that US citizens who meet either the "domicile rule" or the "330 day rule" still owe federal taxes on everything above $87,5000. And many will owe state taxes on the full amount of income. But Nadine would be making under the cut-off income and after one full year and falling under either category of exemption she wouldn't owe federal taxes. She still must file, of course.
Mandi