Upgrade scripts are failing with the below errors:

POST Response : url=http://10.30.170.113:8181/restconf/operations/arbitrator-reconcile:get-active-bundle status=501, reason=Not Implemented

https://jenkins.opendaylight.org/releng/view/netvirt-csit/job/netvirt-csit-1node-0cmb-1ctl-2cmp-openstack-queens-upgrade-snat-conntrack-aluminium/88/

https://logs.opendaylight.org/releng/vex-yul-odl-jenkins-1/netvirt-csit-1node-0cmb-1ctl-2cmp-openstack-queens-upgrade-snat-conntrack-aluminium/88/robot-plugin/log_full.html.gz