That equates to around 280-thousand results being changed.
It's part of a moderation system - brought in after exams were scrapped during lockdown.
In England, pupils who aren't happy with their results can appeal to use their mock results instead - but details of that process haven't been announced yet.
They'll be able to apply for their mock grades to be used, or sit exams in the autumn.
Laura is a pupil from Twickenham, and has this to say about her experience so far.