I would keep in mind that 2019 was the first year of the current maths A level specification taken by a full cohort of stuents (rather than the handful of FM candidates in 2018), the first year of linear instead of modular A level maths. Candidates and teachers were taken by surprise in 2019 by how different the exams were in comparison to what had gone before, Text books and practice papers from Edexcel didn't really point accurately to what to expect. As a result, a lot of people found it hard and grade boundaries were low. Although there was variation from year to year and unit to to unit in the previous modular specification a mark closer to 75-80% was usually needed for an A. All exams since have been affected by Covid and grade boundaries have been similarly low. Edexcel did a lot of work on their papers to make them more accessible and there are now much better resources and a range of Mock, Practice and Past Papers to revise with. While grades awarded will likely match the distribution of 2019, it would not surprise me if Edexcel maths grade boundaries start to creep up this year and in the years ahead.