Back story: Historically my electricity supplier worked on a 3-month billing cycle. They asked for a meter reading (or took their own reading), sent a bill, and I paid it. Rinse and repeat every three months with no problems.
A few months ago, the supplier unilaterally changed to a 1-month cycle. (I suspect their reason is to "encourage" all their customers to install smart meters and to authorize payment by direct debit, but that is beside the point of the question. Neither smart meters nor direct debit payments are mandatory).
The first iteration of the changed system was as expected: supply meter reading, receive bill, pay bill.
Since then, I have been getting monthly requests for meter readings. I supply the readings and get confirmation that the supplier has received them. However I am not receiving any bills. Indeed, each monthly request for a meter reading has an explicit statement that my account balance is £0.00.
The first time this happened I assumed it was just a glitch in their new system, but it has now been repeated for several months.
All messages and payments are electronic (as they were in the previous system), so there is no physical paper trail.
The company website contains a copy of logs all messages sent to me, and there are no messages that were sent but never received (e.g. lost emails).
Do I have any legal obligation to tell the company they are supplying me with free electricity? (Ignore any ethical or moral considerations).
Of course, if and when they company does discover its error, I have no problem with paying the arrears.