Given the CAG/calculated grade problems in 2020, it's unlikely that 2021 exams will be cancelled. There's lots of debate about how they can be made as fair as possible, e.g. cutting down the syllabus or having more optionality so all students can find questions on areas of the syllabus they've covered. In addition to all that, I think it would be good for each student's certificate to (optionally) include a personalised Covid disruption statement from their school to indicate how many teaching days they lost due to ‘circumstances related to coronavirus'. This information is formally recorded in attendance registers so would be easy to provide and would help to put individual results into perspective.