Cambridge Pre-U has not been designed solely for the most able A Level students. It is aimed at all candidates who aspire to study an academic subject in higher education.
Grades M1 to P3 of Cambridge Pre-U are equivalent to the current A Level range, M1 being the current A/B boundary, and P3 being the E boundary. The grades D1 to D3 give greater differentiation at the top end of the range.
In fact teachers are telling us that it is often candidates of a more moderate ability who are benefiting, as the linear structure allows more time for candidates to develop and allows teachers more time to offer support.
Further information can be found in the Cambridge Pre-U Guide for Schools.