At least for purposes of the American Opportunity Credit, Publication 970 says:

"For at least one academic period beginning (or treated as beginning) in 2024, the student both: ...

For 2024, treat an academic period beginning in the first 3 months of 2025 as if it began in 2024 if qualified education expenses for the student were paid in 2024 for that academic period. "

https://www.irs.gov/publications/p970#en_US_2024_publink10003173