I still have to ring QTAC to get more of an idea. but my question is, how can two different uni's give two very different ATAR scores?
Not sure if it’s the same in QLD as it is in VIC, but the way unis calculate your ATAR is a bit different if you took a non-standard pathway. Since you did the diploma, some unis will consider it when considering your admission and contribute differently compared to say, a QCE subject. On top of this, you likely took QCE while it was still under the OP system, which unis often translate this to an ATAR differently.
Other than ringing QTAC and getting someone to tell me what my score could be over the phone is there a way to get a more official ATAR?
I’m not sure, but you could see if you can get a proper QCE certificate via QTAC while you make that call, or try contacting QCAA for the same thing.
The ATAR system is relatively new in QLD; it’s only a couple of years old and there’s only last year’s data to go through (which, as you can imagine, may not be the best representation of a normal year).
Hope that helps!