
I'd say it was 3. end of academic year. As I see it, you are enrolled in the University until the end of the final term. After this date, the academic year has ended and as you aren't enrolled for the next year you have left the University.
Although as others have pointed out, best way might be to ask them... but if you really don't want to then at least options 2,3,4,5 probably fall within a month of each other so you won't waste too much time just by waiting until a year after the last date.
 
	