This read-create INTEGER enum lets an administrator issue an operate command to this physical PRA port, choosing among block(1), delayBlock(2), and unblock(3), per the object's brief description. Administrators write block(1) to immediately take a port out of service for maintenance, delayBlock(2) to block it gracefully after current calls complete, or unblock(3) to restore it to service. Setting this to delayBlock(2) before a maintenance window would let existing calls finish before the port stops accepting new ones.