Fuse 7.12 blueprint properties not getting resolved

blueprint property place holder not getting resolved
For example bundle rest configuration.
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<camelContext id="xx.yy.zz.integration.hello" xmlns="http://camel.apache.org/schema/blueprint">
<restConfiguration component="undertow" host="app.http.host" port="app.http.portNumber" />
<rest id="restConfiguration" path="app.url.contextPath">
--------------------------------Rest configuration shown return this.
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karaf@root()> rest-registry-list xx.yy.zz.integration.hello
Base Path Uri Template Method State Route Id
--------- ------------ ------ ----- --------
app.url.contextPath /hello get Started restGetPerson
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tried with ${app.http.host} but still not getting resolved