The CBSD sends a request to relinquish a grant when:
the heartbeat response includes a terminated grant message
the heartbeat response includes an unsync-op-param message
changes in any radio parameters are detected
the CBSD holds a grant and the user issues the cbsd-authorization shutdown command
When a relinquish request is sent, the 7705 SAR-Hmc re-enables the dynamic filter on the PDN router interface to stop the SR OS traffic and allow only SAS control messages over the interface.
After receiving a relinquishment response or after 30 s, whichever comes first, the CBSD initiates a new grant request to reauthorize with the SAS.