As per the letter the hotel indeed sees club as basic room + club benefits.
De facto they always give you at least on of the nicest "premium" rooms (just below junior suite), or you can get lucky and receive anything above.
So here you don't really know what AMB brings you precisely as an upgrade.
Has that always been the case prior to this week? I am pretty sure I read somewhere that this hotel was one of the best places to use Ambassador status as you would most likely go Club Room>Junior with Opera View.
I understand they implemented new categories/changes this week but I feel being told the Old Club rate was a basic room so I am only entitled to a Classic with Balcony isn't really an upgrade or what was being implemented when I booked.
Maybe I am wrong..