I got an apology from Haven by email yesterday afternoon. I had mailed them demanding a full explanation earlier in the day. They didn't explain the error, just that TRS was halved for November, but said all affected customers are being written to with a detailed explanation. Said the additional amount taken will be refunded by 20th November at the latest and, as their error put me in the red, they will refund any bank charges also. Said my December payment will revert back to my normal amount. At least they had the decency to apologise! As previous poster said, human error happens, it is how it is dealt with that matters at the end of the day.