The word on the FB forum is that FB uses point of sale restrictions in a way that can make inventory available to FB members but not SM redemptions. The thing that I don't know is if the POS restrictions engage based on trip origin when searching on the FB site or if it's done some other way. VA also uses POS restrictions, but it's very clear when using the Velocity Rewards site, as there will be days visible for awards if searching SYD-LAX-SYD that don't show up if you do LAX-SYD-LAX searches.

In trying to use an SWU, I had multiple agents lie to me and tell me that O inventory was not available that I could see on DL.dumb (in addition to EF and FB) and that a colleague saw moments before or moments after. Long sells are not a solution to AF/KL award inventory issues. Seems that it's HUACA or book on DL.dumb.