we are not talking about the

"During the I485 process, you need to stay legal without gap. Now you've lost your own H1b, therefore, you need to move to a different legal status as soon as possible."

This statement is not true. Once 485 is submitted, the person's stay in the US is legal regardless whether he or she has another valid nonimmigrant status. Therefore, she doesn't have to change to another status. She is fine how she is.