Originally Posted by
steve170461
now as Gold I know that I would automatically be put in to C if booking Y
You will probably be overtaken by events : as of 2 April, bmi will have the A330 on the LHR-CAI route, and so BD*G's will (according to the rules, at least) only be entitled to a complimentary award upgrade to Premium Economy, not Business.
ANA does not show PE, so you will either have to check on bmi's 'el magnifico' online redemption website (if indeed that route is listed), or else call the ICC.
Edit to add : the bmi online site does indeed show availability for LHR-CAI in all 3 classes (Y, PE and C), just note that PE is labelled "New Economy".