A friend needs to reactivate their Openreach PSTN line and port the phone number back to that line - without risk of losing the number in the process.
They are currently on Gigaclear FTTP and Vonage VOIP. They do not want to exit Gigaclear at the moment - but also do not want their landline phone to be subject to internet outages and power cuts. Local mobile signals from all networks are very variable.
Is there a risk of them losing their landline number if they simply place an order with an ISP to reactivate the PSTN line and enter into the lowest cost broadband and call package they can find?
If there is a risk, how can it be eliminated?
Thank in advance for any advice offered.