If you do NOT have a break between academic years, then you only need the date the year starts.
The SQL would look something like this;
"Select top 1 from TblAcademicYear where DtStart <= #" Format(Date(),"MM/DD/YYYY" & # ORDER BY DtStart DESC"
If you DO have a break between, you will want one that uses the END date so you can update the year that has ended as well as pre-loading the upcoming year.
As I have to deal with semesters, I do the same but I only worry about semester (Fall18, Spring19, Fall19, ect..).