Full-time student - 5 months enrolled?

My daughter was a full time student at a university in 2022.  Her classes ended in April and her graduation was May 2nd.  Is she considered enrolled for 5 months since she graduated in May or enrolled for 4 months since classes ended in April?   Her earned income was less than half of her support.   So if she was a full time student, she is not eligible for the refundable portion of the American Opportunity Credit.  If she was not a full time student, even with earned income less than half her support, she is eligible for the refundable portion of the American Opportunity Credit.  This question also impacts whether I can claim her as a dependent.  There is no scenario where I can claim the AOC due to income.