Economy 7

The immersion heater light stays on till 8.30 now clocks have changed. I understand it should heat water from midnight to 7.30 on night rate electricity 8.7 p per kWh?
How to I get this changed, it’s just an on off switch. Do I need to get an electrician in every year?

@Jan2019

Night rate doesn’t change with summer time on old meters (not sure about Bulb’s smart meters). So your 00:00-07:30 GMT becomes 01:00-08:30BST.

You could check which reading is incrementing to confirm?