Scroggs
Just out of casual interest, when you order the fuel do you take into account the increasing number of likely level restrictions you are likely to encounter once you hit UK airspace? One of the ones you managed to avoid yesterday was FL310 level by LARDI, designed to get you below London Sector 11 into Sector 10. Great idea from an ATC point of view but not a great help to your fuel burn figures.
In an ever increasing traffic environment these restrictions are becoming more frequent and whilst every controller I know would be happy to help you out if you suffer greater than anticipated headwinds, if the practice starts to become commonplace the goodwill will evaporate.