During the summer it is usual to turn your storage heaters off, as it is usual to turn your gas central heating off. But you keep your immersion heater on for hot water. In the summer some people with gas central heating keep their boiler on just for hot water, while others turn their boiler off completely and use an immersion heater for hot water.
Storage heaters work on stored heat, so if there is no heat stored in the core they cannot warm the room. If you get an unexpected cold day in the summer you can turn on your gas central heating and the house starts to warm up, but you cannot just turn on a storage heater and expect to get instant warmth. So Quantum heaters also contain a built-in ordinary ultra-quiet fan-assisted convector heater. You turn this on and the room is warm in a few minutes, faster than your central heating can warm it, and you need only warm the rooms you want to warm, when you want to warm them. But you are of course paying for the electricity used at the full price not the interruptible energy price, so it is a good idea to check the weather forecast, so that if it is still going to be cold tomorrow you can turn the storage heaters on in any rooms you want to be warm. An app for your phone could alert you but I am not certain that it would be a good idea to allow it actually to turn your heaters on and off.