Oh, darn! I noticed that 4 SWUs were not deducted for a recent itinerary. I waited a few weeks, and they were still there. Since they were expiring at the end of January, I applied them successfully to a couple of domestic itineraries. I figured that they had put them back into my account. It's happened before and I've used them with no problem. Even had a ticket counter agent at LHR once tell me he wouldn't be deducting the SWU, so I could save it to use later. Guess I'll just keep my mouth shut and see what happens, but if they take them back I just hope I have a choice in how they make me "pay" for the upgrades.