If this has been discussed I could not find it, but in searching ExpertFlyer for C inventory ORD-LHR in early January, the EXP desk offered me upgrades from coach to business using SWU's even though no C inventory was showing on the flights (thirty seconds before the call and just after the call). Was I INCREDIBLY lucky to get seats released one or two minutes before the call, or is there some extra C inventory available to EXPs that does not show up on ExpertFlyer.