Champagne is not part of the WT+ product - it is water / oj or sparkling wine out of London as I understand it. CIHY has previously explained the issue is todo with the way BA load the sparkling wine (in London). The PDBs for J and F are as I understand it loaded into a non bonded trolley drawer / insert or something locally and should be loaded chilled. It's like no hot meals on mid haul Moscow flights in WT originally only on A321 because 'there isn't the galley space as it is return catered' when bmi mysteriously managed it by hold loading it and switching catering around during turnaround.
Where there's a will there's a way isn't there...but where there's no will there's no way.