Ours from the DP in the BT Chamber, over to and up pole to the Manifold then over to the gutter of our home, down the wall to our CSP and that took about 43m of tubing give or take a meter or two.
So I would say not lower than that length, 65m like others are saying sound about right.
I think he's asking about the unsupported span from the pole to the premises.
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