In a normal town, the circus usually comes in for a week, month or other set amount of time. However it seems that in Wimbledon they have their own resident circus. We know this because both Lynne and her friend seem to be familiar with Charlie, an employee of the circus. Lynne's friend knows him well enough to be offered a lift to work and Lynne knows that he doesn't own a car. How did she get hold of this information? Perhaps she regularly sees him walking around town.
We must presume that Charlie is in charge of the elephants at the Wimbledon circus, but is he really allowed to give unauthorised rides to ladies? There must be some sort of manager or owner who would veto any use of the elephant for personal gain. The other explanation is that Charlie owns the circus, but this can't be the case because he is known as Charlie from the circus and the elephant trainer would be furious at Charlie pulling rank on him and taking the elephant out.
Lynne's friend must work somewhere that is situated where she has to walk into town first. It appears from this that half the work has been done to get to town in the first place, in order to get a lift with Charlie. Will Charlie ride her right up to the office, or just to the end of the park? It just doesn't seem convenient. Lynne's friend obviously either has the hots for Charlie or just really wants to ride on an elephant.