@helpplease12 The installation's do normally follow the incoming old cable route if that is how your current OR Infrastrucure is and the Fibre cable is general laid up to an outside wall CSP that OR fit external, straight through the wall with a hole that the drill for a short Fibre cable entry and the Mounting off the ONT to connect the Fibre and you Sky Hub with a short supplied 1 to 2 Metre Ethernet cable connection.
OR look to have near this ONT position TWO power socket's one for the ONT and one for the sky Hub, this is all down to the Internal cable lengths for the devices!
Installation day video below may show you what is involved on the day, so take a look this is the Openreach one, CityFibre would be very similar!
Full Fibre Broadband Installation Guide | Openreach
CityFibre Installation | The Full Fibre Broadband Network | CityFibre
You can so NO, there is a danger in doing so, as if OR are withdrawing all the copper then you will be left with NO connection, it is something that they do take serious but it can be for all other kinds off circumstance that YOU as an end user have NO control over.
You just have to hope that where the new ONT get's installed that the wi-fi is as good at working, and if your sky hub is at the same place and working correctly no problems the Copper/Fibre change will NOT effect that way! It's the Hub was in a central position worked great covered the whole home, now they stuck it at the front room and it's ((sugar)) operation for coverage!
