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I don't mean to be too cute in this answer, but I would:
1. Set the battery max to 60% (this needs to be done just once).
2. Check the charge level before leaving car. If <25%, plug in (otherwise don't).
3. Use time-of-use settings on your EVSE to start charging at 12:00 am
Voila!
In fact, this is what I do, except I use a 70% max battery setting.