Easy Action's website lists this new release as being taken from the Oakland broadcast:
http://www.easyaction.co.uk/artists/product/509-roxy-music-showing-out-live-concert-oaklandEasy Action already released the Denver show as Concerto, so I doubt they would make the mistake of releasing the same material masquerading as Oakland:
http://www.easyaction.co.uk/artists/product/60-roxy-music-concerto-cdCarlton P. Sandercock, who owns the Easy Action label, has specialised in grey market releases for over 20 years. He was one of the key players behind the opening of the MainMan archives (Bowie at Santa Monica '72, etc.) in 1994-95, so he has form in this arena. Whatever you may think of grey market releases, Sandercock knows his onions.
Unless JO'B knows something I don't about this forthcoming release, I'd say his entry on the main site is incorrect:
http://www.vivaroxymusic.com/albums_112.phpTo answer your question, I believe this is the first semi-legit release of the Oakland show. All others (Concerto, etc.) are taken from the Denver broadcast.