My current supplier's system will automatically bill me based on a submitted reading. There is no agreement involved. I put in 2152 I'll get debited 2026 to 2152's worth of gas.
I don't see what is to stop the outgoing supplier to wake up to the fact that I've submitted the closing reading of 2089 and invoke their direct debit.
At this point I will now have a (winnable) fight on my hands.
As above. Incompetence.
Of course and it will obviously have to be sorted once I'm clear that my account with the outgoing supplier is closed which is where I think I came in with this thread. I could of course cancel the DD authority but in my mind I clearly have units of gas that are due to the outgoing supplier so if they did bill me I'd pay it on condition that they tell my new supplier that reading.
Note the outgoing supplier estimates an an annual usage then DD pro-rata during the year and I think this estimate is what they've submitted. The new supplier bills monthly on my meter readings (or their estimate if I don't submit one).