XDCR to remote buckets continues even after the cluster reference is deleted

Scenario and seen behaviour
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• Under XDCR tab, add remote cluster reference and then setup bucket replication.
• Watch outgoing XDCR mutation graphs and item count on remote cluster
• Delete the remote cluster reference, replication continues to happen to remote buckets on the deleted cluster, no errors/warnings thrown

Expected behaviour
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'Remove' cluster reference should stop all current replications to the cluster to be removed . A warning should be thrown to the user indicating this, when the user clicks on 'remove' against a cluster reference.