A Brightline student cancels because the exam date moved. The tutor has already prepared a practice set, the family still wants the session, and another student is waiting for that hour. The empty calendar square is the least useful description of what happened.
Preserve intent through the change
Cancellation, postponement, and churn are different states. The reason determines whether to reschedule, save preparation, offer the slot, or close the relationship.
Move the time without losing the work
Sepia keeps the preparation with the student, offers Amina relevant new times, and prepares the waitlist message for approval. One change can serve both families without treating either as inventory.