Hello Duncan Evans,
We do not support recurring events. This feature will be available from Sitefinity 4.0 - for Events. For 3.x you can implement some custom logic that will do this. You can create a new tag, category, metakey or some other identifier that will be used to get all recurring items ( say each month from 1 -5 this items should be visible).
Then you need to get all events that are tagged and check the DateTime.Now. If a given event is expired and today is the 1st of a month you need to use ContentManager to get the content. Then change Event_Start and Event_End dates metakeys using SetMetaData method where the value parameter is DateTime.Now.AddDays(5);
All the best,
the Telerik team