Sainsbury's switch DD is 8x predicted amount

A question about : Sainsbury's switch DD is 8x predicted amount

Has anyone been sent the Direct Debit request from Sainsbury's big switch and had a much larger amount than they should have?

My personal projection from Sainsbury's sent on 03/02 had
Ј350 p.a for electricity
Ј105 p.a for gas
(2 bed new build flat, so low user)

This amount divided by 12 should equal a DD of Ј37

I've received a DD request on 24/02 stating that they worked out my usage and divided by 12 and came up with the following per month:

Ј30 for electricity
Ј76! for gas

So they want to charge me 8x the predicted gas usage a month. Considering I was paying Ј50 a month before I switched, Ј105 a month is not a saving.

I've tried calling them but 3 amounts of 20 mins hold times with no answer means I gave up.

Has anyone else received amounts much larger than expected?

Best answers:

• How long have you been at the property?
  Without accurate consumption data setting a DD is entirely guess work. This Sainsbury's offshoot of BG appear to be very fiscally conservative (they ask most people for 3 figure deposits) so what you've said doesn't surprise me.
  How is the property heated? If it's gas, Ј105 pa is unfeasibly low. Even if it is electricity, Ј350 is at the very lowest realms of possibility.
  Ultimately you'll only pay for what you use, so if your DD is initially too high, you'll get it back.