You can summer prune (end August early Sept) when you have the long whippy growth as in Doves last picture. This will slow growth down, and also make it easier to manage in the future. I agree it needs pollarding first though.
There looks to be a crows nest in the tree, and they will be back early next year. It will be illegal to chop the tree then, so i would get it done soon.
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Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.