This is a long shot but I wonder if your IHD is simply converting the standing charge that is probably applied just after midnight into that much worth of consumption on your IHD. Can you look at the overall cost so far at 1am and see what that is? Looking at my unit rates and standing charge then a cost of around 40p would be in order for that hour after consuming a baseline of around 150w after the standing charge is applied. If I had really consumed 1.06kW in that first hour after midnight then with the standing charge applied it would show around 68p on my IHD at 1am.
Other than that, I concur with @Mailman and I would advise downloading the Hildebrand Bright app to see you actual historic consumption down to half-hourly intervals.
EDIT.... The more I think about this, knowing IHDs aren't very hi-tech, I've read before that they cannot add standing charges to the cost that shows on the display. My charges as shown on my IHD do take the standing charge into account so just maybe that extra (fictional?) consumption is added after midnight to produce a real cost to the user as they monitor the IHD. I wonder if anyone like @retrotecchie or @theunknowntech can offer an opinion on this.
Last edited by JoeSoap; 28-10-23 at 13:28.
I'm an Eon Next dual fuel customer with no particular expertise but have some time on my hands that I am using to try and help out a bit.