As i know hyperoptic may be using a different technology or protocol for their VOIP service compared to the traditional PSTN (Public Switched Telephone Network) that BT phones are designed for. BT phones are typically analog devices, while VOIP requires digital compatibility. BT phones may not have the features or settings required for VOIP service configuration, such as SIP (Session Initiation Protocol) settings or support for encryption protocols.
Using an RJ11 to BT phone socket converter, while it might physically connect your BT phone to the VOIP service, may not address the underlying compatibility issues mentioned above. In some cases, it may work to some extent, but the quality and reliability of the calls may be compromised. . They can provide guidance on whether your particular BT phone can be made compatible or recommend VOIP-compatible phones that will work seamlessly with their service.
food for thoughts
