Super excessive gas bill

RFW

Fairly long story but I'll try and keep it short.

Feb 2010 received excessive gas bill, as I'd been away between December and mid January and had no gas on it was about 5 times what it should have been.
At the same time I also submitted an electricity meter reading. (both from same supplier)

Then a problem emerged, meters at the property complex were all incorrect, about ten adjacent properties all had wrong labels on the meters and it wasn't just a case of swapping them over.

Investigations went on.

I should point out that the property had been vacant for about half the period between March 2009 (when we moved in) and February 2010 and no supply on during that period. Also its a well insulated modern place so the usage is pretty low too.

Its a mixed development, so whilst we live in a 2 bed flat, there are 5 bed town houses adjacent, so I could have had their bill.

Anyway after much pestering and being passed between different departments, they finally supplied an up to date bill which showed £450 electricity and £8000 gas!

Obviously I've complained and await hearing back, I've also contacted the ombudsman, but from what I can gather they won't help until the supplier says they can't do any more.

So what else can I do?

Any help or guidance would be appreciated.