Quick datapoint. Good friend is en route from LHR-SEA today. He was booked in WTP and inquired about an upgrade to CW at LHR lounge. Was offered, and accepted, at 499GBP. He inquired about this at his origination from Geneva, but they had no such powers there, it seems--had to be done in LHR. He did not see a POUG offer while doing the online check in, but that might not have come up since he has a leg operated by AS from SEA-PDX...