When is it correct to say that you're a 'uni student'?

[JR_StudyEd]

I have finished Year 12, but I am still over 6 weeks away from starting uni. I have enrolled in a course, but I obviously have not started studying. When do I stop calling myself a Year 12 graduate and start calling myself a university student? O-week? First day of classes? Would my university consider me to be a uni student right now?

* I am not trolling, this is a serious question.

[r1ckworthy]

I would say that if you have enrolled in your units for your specific university course, configured your timetable etc. then you are officially a uni student!

[K888]

Yep, if you've enrolled in a course that makes you a uni student

[sarangiya]

I'm just wondering what you mean by "calling yourself"?
When I was where you are, if anyone would ask I would just say "I'm starting university this year". Same at the moment, "I'm starting my second year at uni this year".