PitchingFan raises some good questions. One point to keep in mind is that making a last-minute decision to enroll somewhere this Fall if it's not where an athlete wants to end up could have consequences on the athlete's future eligibility.
For example, if an athlete (in any sport) leaving a Division I program would choose to enroll at a junior college this Fall to live at home and save money, they would be triggering the "4-2-4" transfer rules which might negatively impact their eligibility at the next college that they attend depending upon various factors.
In a similar manner, there could be negative consequences if an athlete transfers from a D1 program to a D2 program this Fall as an "interim step" and then would move to another D2 program.
In most cases, there's no going back once an athlete enters the Transfer Portal. It all depends upon the coach.