The route itself, sure.

When this specific helicopter/mission joins the route, how fast it goes, what callsign it uses, when it leaves the route, etc. may not be so public. Or at least be treated as "try not to make it unnecessarily public".

Overclassification is absolutely a thing, too. I recall when the Snowden NSA leaks came out, government employees were still forbidden from reading the documents, even if they were published in the newspapers. Pointless? Yes. But those were the rules.