U.K. power Networks.
This -
“Power cuts might be uncommon, but they can happen all-year-round so it’s important you are prepared and know what to do.
Emergency power cuts are unlikely to happen, but if they do it is important you know:
You will have no power for at least three hours at a time, once or twice a day.
Priority Services Register customers will lose power in an emergency. Being on the Priority Services Register does not offer you any protection from the national power cuts.
Your gas boiler, heat pump, broadband and home phone will not work during the power cut.
Due to the national scale of the power cuts, UK Power Networks cannot supply generators/backup power to customers for these emergencies.
To prepare you should:
Find your block letter (and rota, when published) at powercut105.com.
Keep a mobile phone fully charged (if you have one) so you can use it to go online for updates or call if you have a power cut.
Keep a torch handy in case you are without power during the night.
Have warm clothes, blankets and food which doesn't need heating accessible.
In the unlikely event you do ever experience a power cut call 105 or visit the 105 website for more advice on what to do.”
I was going to ignore it as I don’t think it will happen, but then thought better of it.