I have recently switched to digital voice. One main phone connected to the hub downstairs and the cordless phone is connected using an adapter provided by bt upstairs.Before when the phone ring’s downstairs my husband will answer and I will pick up the cordless one upstairs. Now when the phone rings I can only use one whichever one I pick downstairs or upstairs. I prefer to use the cordless one and it does matter which one I can reach quicker. After 5 rings, it goes to voice mail.I wish I did not renew my contract and waited for bt to make it compulsory being elderly.
See messages 19 and 20 in this thread https://community.bt.com/t5/Home-phone-including-Digital/Multi-call-option-Digital-Voice/td-p/231470...
Unfortunately there is no connectivity between the socket on the hub and the adapters.