PDX being a predominantly leisure route which is also subsidised by the city of Portland, I believe it's fair to say BA have already been paid up front for operating the service. I suppose it's also fair to say there'll be more I and R class fare purchasers on this route than full fare C and J class ones. The advance purchase requirements of a lot of the lower priced Club fares for your travel date are probably now past and revenue management feel the current Club loads coupled with their predictions that not many more will be interested in stumping up £10k for a return from now until departure to fill the cabin will warrent some proactive offers for seats which would otherwise remain empty or given away in the form of operational upgrades on the day if WTP is oversold.... at £400 for a 9hr flight, I'm sure they won't be around for long.