An A isn't always 80%. Understanding boundaries changes how you target your revision.
Grade boundaries are the score thresholds for each grade in a given session. They move every year because papers vary in difficulty.
The practical takeaway: chasing a fixed percentage is the wrong target. Aim for the boundary, and know how many marks of cushion you have.
When you self-mark on SuperExam, we map your score to the boundary for that exact session — so an A* on an easy paper and an A* on a brutal one are scored fairly.
Use the gap between your score and the next boundary up to decide where one more mark is cheapest to find. Often it's a method mark you're leaving on the table.