Looking over the quantitative modules, you'll eventually develop some of the core A-level syllabus and then some more mathematical methods at the university level beyond that. None of it is particularly complex however and it doesn't seem to be an overly quantitative/technical course so I imagine there will be a reasonable amount of support.
Specifically you'll develop single variable calculus and algebra as in A-level, and then do some multivariable calculus (partial derivatives and constrained optimisation). It doesn't look like it develops matrices, complex numbers, or any higher mathematics in that vein.