In a calendar-driven curriculum, chapter three arrives in week five for everyone. Mastery-based teaching inverts the constraint: what is fixed is the required standard; what varies is the time taken to reach it.
A student who already has command of a module validates it and moves on. A student who needs time takes it again, differently, with other exercises and another angle of explanation, until validation. Both reach the same certified standard.
The approach has been known for a long time, and it demands a great deal: continuously diagnosing each learner's level, producing different exercises for different profiles, keeping a record of every skill. That is precisely what the digital campus infrastructure makes practical at scale.
Teachers gain back the time the mechanics used to take, and spend it on what needs a human being: supporting, correcting a line of reasoning, restoring motivation, adjudicating an assessment.
We accept the consequence: the durations we announce are design markers. A fast-moving student finishes earlier; a student working alongside advances at their own pace. The award always certifies the same standard.