I'm still curious where these mystical gems are. As indicated previously, I can't find them on the landside-airside security gates (and I've checked again since my post to make sure they aren't there!)

So when I'm at T5 later this week, do I have the right to use FastTrack (BA Economy, Qantas Platinum (ie oneWorld Emerald, or the "equivalent" of BA Gold)) [and if so, how do I prove my entitlement if asked?], or do I definitely have to go through the normal queue?