I haven't been in this position myself but my understanding from reading up on this a while ago was its best not to pay it off at this point.
She will slowly pay it off as a 'tax' on her income and if her circumstances change later and she doesn't earn as expected (due to job taken or starting a family) she wont pay it all back. I think id at least wait until she is finished and a couple of years into a job before making a decision when she/you have a better idea of earnings.