Originally Posted by
IanFromHKG
No, you aren't allowed to use the arrival lounge, since arrival lounges are excluded under oneworld rules. Sorry.
It is technically possible to use a departure lounge on arrival, but you then have the problem of getting a staff member to escort you back through immigration to go landslide. You can search for threads on here to find out how. But it is not encouraged.
I was under the impression that business class passengers were entitled to arrival lounge access. Have things changed recently?