Attendance here isn't a statistic, it's evidence. A grading requires a minimum number of sessions, and nobody wants to reconstruct that from a notebook three weeks before the date.
Enrolment is the September bottleneck. When the form, the parental consent, the medical note and the first payment arrive together online, the week before term becomes work instead of chaos.
Family rates and sibling discounts are the norm and the commonest source of billing errors. Held on the family account rather than recalculated each time, the month adds up without anyone going back over it at the kitchen table.