Let's deal with next years Y13's next year. The immediate problem is outgoing Y13
Whilst I agree this year's Y13 grades do need sorting out - that needs to be done ASAP.
But next year is too late to be sorting out the new Y13s and their exams too. They need to be working on this, this year. They need to be sorting out ahead of time and figuring out how to help those kids who have missed several week's of work time but who will be expected to sit full exams. But the exam boards could be set that task perhaps - or at least for them to put some proposals forward which would help reduce the disadvantage students may well be facing.
Same with the GCSEs. Year 11s need to sorted ASAP - and again we are talking within days as weeks and months is no use to these children.
And then the new Year 11s and the exams asap after that, but again next year is too late.