I am with Eon via tesco for tesco clubcard points. I was £85 in credit last month, and they suddenly increased my DD from £78 to £120. I called them up and they reduced it to my suggestion of £100. I did not have to argue the point at all. In the current climate I don't think they can afford to lose the business. I tend to get about 3500 ba miles a year from Eon.
Obs