... and now I've received a real bill, asking for £90 payment, with no meter readings at all - not even estimated ones! It just states that they've guessed at my annual usage and divided it by 4 to get £90! Are they wanting to just forget about the previous overpayment?

I've no problem at all with estimated bills and I'd rather pay £90 than move all the things necessary to get at the meter but that's only because I know (normally!) that, if I'm not paying for the units used last month, I'd be paying for the units to be used next month.

BREWERDAVE1:they perhaps recalculated the estimated amount

No. The "information only" bill uses the same unit rates as the "proper" bill.

I've recently received a somewhat peculiar bill for electricity from EDF. It is "for information only", and it uses "estimated" readings. It is dated 2 August. The bill states that "payments made after 20 April 11 will be reflected on the next bill" and it is for meter readings between 08350 and 08658 between 21 Jan 11 and 20 Apr 11. The amount, £41.44, is different to other recent bills.

I paid up to the estimated meter reading of 09330 in May and an actual meter reading of 08873 was taken in July.

I'm filing their bills somewhere handy but I just wonder who would pocket the £41.44 if I sent them a cheque?

Has anyone else had anything similar? There was a time when I would simply trust the supplier to get things right and pay what they asked for. This bill stood out though because I had been expecting the actual reading to be on the bill, otherwise I could simply have paid them £41.44 and thought no more.