According to the FAQ, any graphically revamped zones will be present in their new form on the servers but could retain the original population. The Sleeper will be in status at the start, the modern user interface will be used, and some of the events, races, and classes will not be available until the server unlocks them.
Daybreak will be running an open beta for the server to test the reduced experience rate that this server will feature. Testers will be treated to some kind of reward, which may be a backpack.[Source: Progression server FAQ]