@shaun55
You'd need to ask the manufacturer/provider of the lift service.
The main issue may be that once non-PSTN service is in place, there's typically no longer call functionality from any internal extension socket.
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Sky Glass 55" (on ethernet) & two Stream Pucks (one ethernet / one WiFi)
BT Halo 3+ Ultrafast FTTP (500Mbs), BT Smart Hub 2
