That makes sense (from their viewpoint!). If I saw that happening to me (and they could not produce a credible explanation), I think I would probably cancel my DD and 'switch' pretty pronto!From past experience when your supplier decides to up the direct debit even though your usage hasn't gone up and your on a fixed tariff its a sign they are having cash flow problems... and are probably on the verge of going bust. Its what happened with two of my suppliers just before they went to the wall.
Kind Regards, John