The Roundup is where the office writes down what it knows about London that will not fit on a zone page. Each zone page answers one question: who is nearest, and how long she takes to reach you. These notes deal with the questions that fall between the zones, the ones guests actually put in a first message. Which side of Oxford Street is this hotel on? What is still open at eleven? How do I get from the towers to a table in the middle of town without losing half the evening?

The first ten are about the map itself. There is a residential map of the board, zone by zone, because every arrival window starts from where she sleeps. There are the boundary hotels that draw on two districts at once, the length of Sloane Street where three zones meet, the Elizabeth line that strings five of them together, and a halfway table in Covent Garden for a guest in the east and a companion in the west.

Then the clock: when each zone winds down, which kitchens open on a Monday, and what the early dark does once the clocks go back. And two evenings with a particular shape, a first night for somebody new to London and an awards dinner in the Great Room on Park Lane.

Every note is written to the same rule as the rest of the site: each claim is one you can check the same evening. Hotels and restaurants are named as places on a map and nothing more, because none of them has any arrangement with this office. The figures are the ones on the rates page, from £250 for an hour, handed to her in person when she arrives. Sylvie writes most of these from the same desk that answers the messages, and more will follow through the year. If a note leaves a question open, send it with your hotel and your hour, and the reply will come back as a yes, a no, or the nearest thing to one.