policy: filters that use query don't work with postules
policy.suffix or policy.pattern filters don't work when policy is evaluated as a postrule, because in the finish phase, req:current() is nil.
One use case that doesn't work is qname filter with reroute/rewrite action in the daf module:
daf.add('qname = example.com reroute 192.0.2.0/24-127.0.0.0')