The first estimates from Qualifications Wales show almost 26% of pupils have received A*-A grades, compared to 18.4% in 2019.

And 74.5% received A*-C grades, compared to 62.8% in 2019.

Meanwhile almost all pupils – 99.6% - received passes at A*-G grades, compared to 97.2% last year.

Firm figures will be released later.

Results were based on teacher assessments, after this summer's exams were cancelled due to the coronavirus pandemic.

It has been a year like no other for teenagers who would have normally sat their GCSE exams.

They were due to have received results using an algorithm, but following a U-turn after an outcry over A-level results, they are now receiving those estimated by teachers.

But there are some students who still have concerns.

"We'll always be known as the 2020 exam year," said one.

It will be impossible to compare this set of results to 2019, which saw nearly two thirds of pupils getting good GCSE grades.

It will also be difficult to glean meaningful data about how pupils are performing in different subjects - or compared with other parts of the UK.

GCSE results will overall be significantly higher, now that some grades will not have been lowered to meet expected averages.

Here’s a look at the proportion of students achieving the highest grades in Wales, year by year.

Ioan, 16, a pupil at Ysgol Y Moelwyn in Blaenau Ffestiniog, Gwynedd, said: "After what's gone on with A-levels, hearing that they've changed it for GCSEs, it's boosted morale for everyone.

"We had our reports a few weeks before lockdown and that's given us rough estimates of where we'll stand. I know what's on my report card - I was told As and double As and A*s in science.

"It was a weird feeling knowing I'd be in the first year not to have to sit GCSEs, with all the preparation we've done in class, but not to have to put in that studying [for exams].

"One side of me says we've not had stress but the other side says it's a cheap way [of getting qualifications].

"We can't actually say we did it, even though I know I've put in 100% and done the work."

After it emerged a quarter of students received lower results than estimated for their Highers qualifications, the Scottish government stepped in - raising alarm bells in other parts of the UK.

A last-ditch move by the Welsh Government to provide a safety net that A-level grades would not be lower than the pupil's previous AS grades failed to prevent an outcry once schools and pupils saw the standardised results.

There was mounting pressure as pupils, teachers and politicians said the process had generated unfair results in Wales.

Although Education Minister Kirsty Williams initially defended the system as fair and "very robust", it was announced on Monday that pupils would be awarded grades assessed by teachers after all for A-levels and GCSEs.

This summer's results were due to be calculated by "standardising" grades submitted by teachers based on their view of how pupils would have done had exams not been cancelled.

We know already the proportion of top grades awarded under teacher assessments is more than last year.

Qualifications Wales set out that 24.5% would have a grade A* or A, compared to final results of 20% in 2019. And 73.4% would have an A* to C grade, compared to 64.4% in 2019.

Dr Rhian Barrance, education lecturer at Cardiff University, said teacher assessments in general should be seen as reliable indicator of pupil performance.

"Having said that, there is some evidence that in some cases teacher judgement might be biased against certain groups of students - those from disadvantaged and certain ethnic minority backgrounds.

"So it's really important when the data comes out it's monitored so that doesn't happen and students have a right to redress, to directly appeal to the exam board not just through their schools."

The surprise element of results day will be missed by some pupils as a result of receiving teacher-assessed grades.

Imogen, from Llanfair Caereinion in Powys, is expecting 10 results but is disappointed that she won't find out what her moderated grades might have been.

She also questioned what future employers might make of the 2020 grades.

"I'm not nervous, excited or worried," Imogen said.

"It's spoilt the day really. When lots of people could now be getting similar results, you ask yourself why have I bothered working for the last couple of years?"

Welcome to our live coverage of GCSE results day in Wales.

It comes after a U-turn over this year’s grades.

Because coronavirus forced the cancellation of exams, grades were calculated using an algorithm, with teachers asked to provide predicted grades.

But last week’s A-level results saw 42% of the moderated grades lower than teacher assessments.

The Welsh Government later said teachers' estimates would be awarded for instead for both A-levels and GCSEs.