You can configure the Secondary site as the Preferred site. The current Preferred site becomes the Secondary site.
Note:
Objects with Data locality=Preferred always move to the Preferred fault domain. Objects with Data locality=Secondary always move to the Secondary fault domain. If you change the Preferred domain to Secondary, and the Secondary domain to Preferred, these objects move from one site to the other. This action might cause an increase in resynchronization activity. To avoid unnecessary resynchronization, you can change the Data locality setting to None before you swap the Preferred and Secondary domains.