Gidday Craig,
Why is it you ask this?
Our Power Board(Sorry Lines Company) here uses the 11pm ON and 7pm OFF, via Ripple control as far as Domestic controls are concerned.
There also used to be the afternoon boost during the Winter too, for 1 hour, 13:00-14:00.
Ray (RODALCO) who is a Vector Faults Technician, nearer to your area(Titirangi), could give better advice.
There are so many ways that Hot Water systems are controlled these days, it's hard to give one blanket statement, mate.
