A warm welcome to our Community Forums and thanks for your post.
In the unlikely event there’s a power cut or a broadband fault, you won’t be able to make or receive calls and most devices that are connected to your phone line (like care alarms) will be affected until the power or network’s back. Due to this, for those without a mobile phone or who may be vulnerable we do provide a back up system. You can read more on this here:
You can view everything you need to know about the switch over here
I hope this helps.
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