I do NOT know, but I strongly suspect that this is yet another of those embedded, but disabled enhancements that Airbus will SELL to operators as a Value-Added Feature. (Don't get too snarky; Boeing pulls this stunt just as often.) The feature is already there, but unless one pays an extra fee, AB (or for Boeing's V.A. features) they simply disable it. Obviously, some operators buy and some do not. This and other features may be included with some software upgrades, or it could be a stand-alone feature, for a 'slight additional fee.' Personally, I think it is a horrible marketing practice but I don't write the rules. This is but
one example of why the fly-away cost of otherwise nearly identical airplanes can vary so much. Please forgive the horrible analogy, but this is little different that purchasing a new automobile; the Up-Sell is substantial, even at the $125Mil level.
