I am going to pave part of my front garden. There are a BT cable and a Virgin
Cable in the area where I wish to pave - both about 9 inches down.

I am wondering if there is such a thing as "snap-on" conduit that I can put
around the cables before I do the paving. If the cables ever needed replacing
they could then be pulled through the conduit they will then be in.

ie rather than putting conduit down and pulling the cables through - put it
around the cables without disconnecting them.