How Do Student Loans and Grants Work?

I have two kids in college (well one just got his AA and signed up for the Air Force, so technically he is no longer in college) so I should know this, but it has been so long since I dealt with any of this first hand that I am stumped.

My son has been going to a very expensive private college. In order to pay for it he has a scholarship, several grants (a couple are school-based) and a massive amount (IMO) of student loans both subsidized and unsubsidized.

He has decided that fancy-dancy school is too hard and now wants to drop out (well technically he already has dropped out) and enroll in the local community college instead.

Obviously his scholarship will be gone, as will the school-based grants, but what will happen to the loans and other grants? I know he will have to re-apply and re-do the FAFSA etc. this year, but for this semester (if he enrolled immediately) and after having received loan and grants that are “annual” but dispersed half each semester. Would he still qualify and receive the full amount (that he would immediately return because it would be way more than he’d need for community college) or would he have to start at square one applying for the loans and grants that he needs if he needed them?

He doesn’t need any loans or grants to pay for community college, so this is mostly curiosity and academic (HA!). I am just wondering “what ifs”.