EXAM boards and education minister Peter Weir are being urged to ensure all pupils receive "fair" grades when A-levels results are published today.
There are concerns that some young people may be 'downgraded' due to the past records of their schools.
A-level pupils have said they are expecting the worst ahead of an extraordinary results day.
With exams cancelled due to Covid-19, young people are receiving results based on predicted grades by their teachers and their schools' historical data.
Exam boards have also moderated the grades to ensure this year's results are not significantly higher than before.
Analysis: Pupils to receive results for exams they never sat
A similar system in Scotland saw First Minister Nicola Sturgeon apologise after students were downgraded with those living in the most deprived areas reduced by 15.2 per cent compared to 6.9 per cent in the most affluent parts.
In Northern Ireland, the CCEA exams board has already said that without standardisation of teachers' predicted grades, the proportion achieving A*-A this year would have jumped to more than 40 per cent. For the last three years, about 30 per cent of entries in the north have been awarded an A* or A.
Northern Ireland is at an advantage over England in that it retained the AS-level as part of the overall A-level qualification. The A-level standardisation model has relied partly on data from AS-levels already taken. Previous research has shown there is a strong correlation between AS and A-level performance.
However, some pupils have voiced concerns that the way grades are calculated in the absence of papers could penalise some.
The CCEA has said it will ensure that its exam standards are maintained.
However, schools will be allowed to use results from mock exams to appeal if they feel a pupil's grade is wrong.
In England, pupils have been told their exam grades will be no lower than their mocks results.
Pupils, parents, teachers, principals and politicians have all appealed for fairness.
CCEA Chief Executive Justin Edwards said this year, due to the alternative arrangements, it was not possible to ask for examination papers to be reviewed as would be normal.
"We recognise that there is robust evidence available on student prior performance and that this could be considered within the appeals process. The opportunity for schools and colleges to submit mock examination information and completed GCSE units provides a broader scope of evidence for appeal," he added.
Appeals will only be accepted from schools, and not directly from pupils.
The National Union of Students said using mock results risked "making a mockery" of the exam system.
Meanwhile, the former head of the Ucas admissions service Mary Curnock Cook suggested it may be a good idea to relax caps on university places.
"The problem for universities - leaving aside the kind of operational mess and everything being late - the problem for universities is that there's been a number cap applied to students because early in the crisis everyone thought that demand for university would be down, whereas now all the indications are that aggregate demand for higher education will be up," she said.
"The problem is that it sounds as if a lot of students won't have their appeal grades confirmed for a number of weeks and that of course makes life very difficult for them, which is why I think it may be a good idea to relax this cap because if a university is up against the cap on recruitment then they're going to have to make some very difficult decisions about potentially taking students who have got slightly lower grades, or waiting and hoping that the appeals come through."
