I just noticed this, which says that as as of 1 July 2017 we now have to declare our worldwide income just to be assessed for HELP repayment -
https://www.ato.gov.au/Individuals/Study-and-training-suppor…
What I'm wondering is what happens if you don't declare your worldwide income?
How did you get HELP if you are not a citizen or resident? Or are you non-resident just for tax? If so looks like you have to lodge your worldwide income if you exceed the threshold.