You are, I believe, hoping that the BT Tech will connect your Cat6 to the drop wire in a box on the eaves and then install the master at the other end.
You may find that the answer is NO ... remember the network belongs to BT right up to the NTE (master) and BT will want to provide the cable.
How easy will it be to pull a new cable through the conduit? Because you may find it necessary.
M H C
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