Monday, four in the afternoon.
The receptionist opens the day grid: the artificial pitch shows the five-a-side league holding all three thirds from seven until ten, as it has every Monday since the season block was entered in August, with floodlights attached to each hour.
A customer at the desk asks for a third at six; the grid shows two thirds free at six for an hour, with the peak price for a weekday evening already applied, and the receptionist takes payment and the system sends the customer a confirmation with the changing-room code for tonight only.
Online, another customer searches for a tennis court on Saturday morning, sees the weekend price, books court three and pays.