As the cheap rate is only 6 hours and not continuous during these 6 hours
Intelligent Octopus (IOG) has a off peak window between 23:30 – 05:30 where you will get a full 6 hours at 7p kWh. This part of IOG is just like any other tariff on the market, where you schedule charging between the cheap rate hours.
The intelligent part of Octopus comes in after the off peak window has finished and by setting a ready by time (8am or 11am) you extend your off peak hours but, charging between say 05:30 and 11:00 is only done when the grid is at its greenes’t or rather has spare capacity, so this part fluctuates when the car is charged/not charged however, theoretically your car will be charged to the set % by the ready by time you set.