We cut ours back once all the fruit is finished. We have already done it. They are cut to ground level. Easy to tell the old canes, they are the dark ones with tired looking foliage.
Autumn fruiting are pruned differently. They are cut down in Spring as they fruit on the new growth made that year, rather on the growth made the previous year.

Same as Owdboggy. I cut them as soon as the fruit is finished and about a couple of inches from the ground.

The old canes that fruited this year cut right down to the ground or just above. The new canes will fruit next year and you can trim the tops if you want to if they are very tall only because the wind can get at them and whip them around and break them sometimes.

Monty Don (on Gardener's World) recommended leaving no more than six strong canes on each plant to maximise the size of the fruit next year