Wouldn’t they only act on this if you had solid evidence e.g bushwalking group has lost a member or something of this nature.I think the 24 hour thing is a common misconception,
when people are missing in bushland searches are usually started swiftly.
I‘m sure we’d all like to believe they’d assist to search for an adult missing for an hour, but I really find this difficult to believe. They’d be jumping at shadows all day long if this was the case.