A wholesale vegetable market is considering holding its auction at five in the morning instead of seven, in the hope that traders will get produce to the retail shops earlier in the day. Which of the following would be of most use to establish before the change is made?

There can be no auction at five unless the produce is standing there at five. If the growers cannot arrive before six, the earlier hour would only leave the yard empty and delay everything, so this is the point on which the whole change turns. The auctioneer's length of service, the number of retail shops and the state of the paintwork have no bearing on whether the earlier hour is workable.