my current fixed price deal with edf for electricity (only) is due to expire at the end of march 2015. I just got a letter from them offering me 2 options when current deal expires. 1. switch to standard variable tariff currently 14.14p per therm or 2. move onto blue price promise valid to may 2016 price, 14.37p per therm.

they claim the blue price promise will save me £51 per year despite the cost per therm being higher. the only way I can see this could be achieved is if I switch to a DD for which they appear to be offering a 6℅ discount.

i currently pay by SO and almost always in credit. (I used to have a DD with them but after they arbitrarily hiked it a few years back again while I was using less electricity than I was paying for – on the dubious grounds that I would need to pay more because they had estimated for reasons unknown that my consumption would increase) – I switched back to the SO.

So I am inclined to stay with the SO. If I go on to the standard variable rate will it disqualify me from get a fixed price rate in future?