Thanks for the quick response.
Yes, either or both these would be good. But just as you automatically select cheap rates for charging, so it would be good to automatically select the most expensive rates for discharging.
As an example, for my schedule tomorrow, I will have completed charging by 4.30, but don't want to discharge until 7.30. Then I would recharge later in the morning at a lower rate and hold until 16.30 when the rate peaks.