Its very odd, this server was built yesterday so it only has IIS and Lucee installed (using the installer mentioned). I did also have IIS rewrite installed (microsoft) - tried removing that but made no difference…
I tried creating a test.cfm with the above code in the Lucee folder - C:\lucee\tomcat\webapps\ROOT and the redirect works fine! so must be IIS?
however the CURL request interestingly looked like this:
HTTP/1.1 302
Connection: close
location: https://www.google.co.uk
Content-Type: text/html;charset=UTF-8
Content-Length: 96
Date: Thu, 02 Sep 2021 19:53:26 GMT
<html>
<head>
<title>Document Moved</title>
</head>
<body>
<h1>Object Moved</h1>
</body>
</html>