Is it possible to make Timeframes stackable?

[markjsmith]

I want to minimise my overnight charge to allow my batteries to take as much solar energy as possible.
Of course, at the same time I want to get the best rates! So my aim is to, at 23:30 each night
Look at the energy I need til 6am in terms of hrs charging, and update my target time frame accordingly. That I can do.
Then I want to look at what I need until 7 and if I need more energy, select more slots and so on through the day. This is where I stumble. I would most probably if I selected 1 slot between midnight and 7, pick one already selected up to 6am. Any thoughts?