DD
I rarely import over the 4-7pm time frame, apart from the occasional blip when boiling a kettle or using a couple of hobs with the airfryer or microwave. That's the problem with the Gen1 inverter and a max output of 2600w. I would have signed up for the DFS, but was out from lunch until the evening and I didn't get the email till 2.30pm, so unfortunately missed it.
I'm on IOG, as are you from memory, and charge the 9.5kW fully overnight. On a few of the really dull days, with only around 1 kW of generation or less, I usually run out after around 9pm and have to use the grid till 11.30pm. If we get upwards of 3-4 kW of generation, I'm usually good till the cheap rate kicks in. That also includes the A2A heating on most of the day, set at 20c and using around 150w-300w an hour once up to temp, with outside temps at 5-10c. We're quite well set up here!