Smart meters and diiferential tarriff like economy 7?

How smart are smart meters?
So if one is fitted, can i can i change from standard tariff to the economy 7 tariff and vice versa if needed, without changing meters at GBP 120?.

I know its a capability and policy but what is the situation re Bulb now and in the near future versus the longer term…

How would this work with a 2 immersion hot water heater , one programmed on a timer overnight for the E7 tarriff the other an adhoc manual temp booster.

How smart are smart meters? So if one is fitted, can i can i change from standard tariff to the economy 7 tariff and vice versa if needed, without changing meters at GBP 120?.

I know its a capability and policy but what is the situation re Bulb now and in the near future versus the longer term.

Yes.

Bulb right now have a 3-rate tariff via smart meter: https://bulb.co.uk/smart/

How would this work with a 2 immersion hot water heater , one programmed on a timer overnight for the E7 tarriff the other an adhoc manual temp booster.

That would be entirely down to your own control systems on the consumer side, which is supplier agnostic.