DMEX process/rules

ElwoodBlues

Currently in dispute with my supplier over gas billing. They've now provided me with revised bills, and now that I've complained to the ombudsman, supplier has just mentioned doing a DMEX and manually generated bills. By googling I've discovered that DMEX probably stands for 'dummy meter exchange'? And suppliers use this process as an override to adjust historic meter readings?

Is there some kind of regulated/accepted process or framework for this procedure? My supplier has decided, completely by themselves, that my opening read (from 5 years ago) was incorrect, so they've done a DMEX using an 'estimated reading' of their own creation, which is completely and utterly incorrect. Now they've rebilled my usage for the last five years (using entirely estimated reading for the entire time), and it's come out insanely high.

Can a supplier actually just do a DMEX without discussion or even notification? Doesn't everyone have to be in agreement (current supplier, previous supplier, customer) for a DMEX to take place?

Reading between the lines, their DMEX was used to alter my gas reading about 2 years ago, after they'd already been supplying me for 3 years.

WiserMiser

Yes. It's The Mysterious Third Party.

https://justsoyouknow.so.energy/posts/2110586-my-opening-reading-is-wrong

It may have made a degree of sense with traditional meters, especially with the old rotary dial ones where even meter readers sometimes got it wrong. Customers were also known to 'massage' their manual readings, e.g. illegally inflating the figure before a price rise to get some future use at the lower rate.

But it's absurd that a reading remotely obtained from a smart meter can be 'corrected' in this way. The obscure rules need to be updated to outlaw these adjustments, readings marked S must always stand unless the meter itself is faulty.

Edit: Typo (maked→marked)

Scot_39

DMEX - or at least meter resets / meter reading forcing events can be associated with meter reading errors at swapover - but can happen at other times - after say long periods of estimated bills accumulate significant errors - or when comes to electric multirate - periods of register / reading / rate swapover.

(Ive had to have SG force meter readings onto old parents account - when I took over under POA - when measurements had been rejected for 2.5 years - logged with a note - rejected manually be CS - on the first reading - which was valid - and so it and others - at 6m intervals - never applied to billing)

Are you sure it is the actual swapover reading they are disputing - as I agree it seems strange that they would go back and dispute this 5 years after the event.

And if so significant - even stranger - the error wouldn't have been identifiable - perhaps even fairly obvious if really big - nearer the time. On old or new supplier accounts.

Or have they now spotted significant other periods of billing errors in the interim - say estimated bills and having to force the system to correct them ?

Just some history

I assume you were happy with the meter readings at time of swapping - vs those submitted - or you would have complained about them then - and not now ?

And that you actually checked both old final bill and new suppliers first bills against your reading and the values used on both bills agreed - even if a little different from your own readings (*) ?

Do you by any chance still have the old final bill / first new bill from 5 years ago ?

(*) FYI in case not aware - A little background - this time from Octopus's descriptions - on supplier swap reading vetting

The handover reading isn't generally 100% in their control -

Reading an old Blog post by Octopus - vs a more up to date post - it does now seem a generally faster process - but still much the same mechanism involved.

from 2017

https://octopus.energy/blog/secret-life-opening-meter-reading/

Given this long description - the swapover reading on the face of it cannot be lower than your last validated reading at the old supplier - only between it - and the projected maximum reading.

an update from same supplier from 2020 with generally tighter time scales

https://octopus.energy/blog/handover-meter-readings/

As above post by WiserMiser - it would be nice to see a functioning smart update - but the third party may not (presumably if not already it could be authorised to gain DCC access) and the new supplier initially - have no access to your smart meter - for days / weeks.

So Applying that description to your case

Did you have operational smart meters at time - or old meters ?

With many smart tariffs and smart meters - the period for any error to accumulate - is likely to be shorter now - my current supplier can get smart readings daily - a new supplier often within days - but generally within 2 weeks.

As to validated - well if that means good enough for "billing" - well my supplier now issues statements monthly from smart meter - 10 years ago - its parent company asked for manual readings occasionally - just ahead of 6 monthly billing cycles - perhaps even an occasional actual meter reader visits readings.

That description would suggest - at least in a normal handover - well at least to me - suggests the new supplier shouldnt then really be able to go below the last validated reading submitted to the third party to agree handover by old supplier - so again - I'd interpret that description as suggesting the new supplier shouldn't then drop below that base validated reading from old.

But on the other hand - I suspect ultimately - there has to be a recovery mechanism - in the event the user got readings wrong (genuine error or maybe not) and/or the third party - got it wrong. But why then taken 3 yrs gas or 5 yrs electric ?

All based on the basic principle being you never pay for the same use twice to both old and new supplier.

As if handover reads wrong but was as normal used by both suppliers - then strictly wouldnt the money they now demand - need to be refunded from old supplier to you (probably sadly not to them directly - as two separate contracts) - to cover a lower than actual agreed swapover reading.

Otherwise you paid old for upto agreed reading xxxxx kWh / m3 on their final bills - and are now expected to pay the new supplier for some of it.

And again if agreed was low/in error - wouldnt that have given you a large refund or simply a lower final bill 5 years ago - so again still in line with the new - so had the cash - at least at time - to pay the new demand at new supplier.

Unless the new supplier got it wrong - and used a higher estimated reading - than you were billed at old supplier final bill. Which if significant surely your next actual or smart reading - or bill / statement from new supplier would have made fairly clear (abnormally low costs for a period - if was too high).

And if so - if new supplier only error

Could back-billing influence this recent demand ?

And just one potential segway - would new back billing potentially protect you from any errors in some way - at least those made by new supplier - during the period in dispute ?

ElwoodBlues

No smart meters involved, it's an older imperial meter, which I still have today. The original handover reading wasn't an estimate - I gave the current supplier meter readings at handover 5 years ago. My previous supplier then billed up to this reading and my account with them was closed, and my current supplier started their billing from this same value. Current supplier has estimated some readings since, I've been lazy and not provided regular meter readings, along with one reading years ago that was wrong as I misread the old rotating dial meter. This has lead to them over estimating usage (by a modest amount) and also increasing my monthly direct debit.

End result is they've charged for too much gas, and even by their over estimates my account was still in credit. So I asked for a refund, and rather than re calculating my bills and refunding my credit balance, they've somehow now decided that the hand over reading must've been wrong. It now transpires they've just done a DMEX on their billing system (for a date two years ago, half way through their time supplying me), to a value lower than the transfer value. In addition to this they've then back estimated to the handover, and come up with an estimated reading for that date as well (along with interim ones for the whole 5 years).

It's exactly as you say - I paid previous supplier for up to xxxx units, and now current supplier is trying to bill me for usage lower than that, units that I've already (correctly) paid previous suppliers for years ago. Not just a bit lower, but a lot - about 120,000kWh worth! Obviously that's more than wiped out my credit balance, and now they claim that I owe them a substantial sum.

I have kept some bills from the previous supplier, including their last bill showing the charges up to handover. It goes back way beyond just the previous supplier though. Thankfully I've got bills going back 15+ years, from several different suppliers, and the meter readings on all those bills are still lower than what the current supplier is claiming it was 5 years ago. Several of these previous suppliers no longer exist.

What do you mean by a 'validated reading'? Last time an actual meter reader came out and took one was well over 10 years ago.

I've been repeatedly asking the current supplier for a refund for about 6 months now, and every time I contact them they just ask for current meter readings over and over. It's only now I've complained that it's come to light that they have recently stuck this DMEX on my account and rebilled all my usage from estimates. I'm surprised they can just do this?

Scot_39

They have to produce a realistic using industry modelling of seasonal use whenever they do a massive correction - they arent allowed to just lump say 2-3 years of over or under estimaing into a corrective bill of say a week (like SG tried with my mum after 2.5 years).

The fact you were in credit could be bad news as far as backbilling protection goes.

But the 120,000 kWh - thats just defying belief - as if electric that would imply they have maybe somehow even included a meter wraparound - depending on your max meter reading - into the mix too.

With some key dates and readings records time now to escalate to formal complaint and i suspect will end up maybe submitting via Ombudsman if necessary.

ElwoodBlues

It's already with the ombudsman, that's how I got the supplier to disclose any billing details at all (supplier has been trying to sort it out themselves for 6 months, keep taking my direct debit, but hadn't shown any billing info). They have now rebilled all my usage, according to their estimates, all the way back for five years. They've come up with quarterly estimated readings for the whole time. But apart from being ridiculously large, they're not seasonally adjusted either. For example they're saying I used £1200 worth of gas between April and September one year, £800 April to June another year. But also saying about £800 from Jan to March.

I do wonder if they've tried to just conjure up estimated readings that would show 'typical usage' and tripped themselves up by forgetting that I have an imperial meter.