Hi
@clegg2000
If i's any comfort, You are not going mad, I've had exactly the same frustration.
It seems that once you've specified a low-cost time period (even for experimental purposes) that you can't remove it, you can only change it. Bizzare.
I don't use Pre-conditioining at all.
The best I could manage was to set a start time of 00.00 and an end time of 23.45 in the App. I have no idea if the car pauses charging for that 15 minutes.