Connectors specify whether or not they will allow the structure to be rebuilt through user-managed rebuild processing (ALLOWREBLD). If user-managed rebuild is allowed, the connectors can allocate another structure of the same name and rebuild data into the new structure. ALLOWREBLD=YES is the default, so if you do not allow the structure to be rebuilt through user-managed rebuild processing, you must provide your own interfaces for planned shutdown before reconfiguring a coupling facility. You also must specifically code ALLOWREBLD=NO, which will prevent a user-managed rebuild from being started.