Pruning depends on the type of Clematis. Simple rule though is if they flower before June then don't prune After June cut back in February.

The last time we moved was in October and I brought two with us. I cut them right down and potted them and they are both doing well but as yours are already in pots, when you move put them in a good sheltered position and plant them out in the spring or early summer. I've not had a problem cutting them quite drastically after they've flowered and both have re-bloomed really well, even at the moment.

Even if they are clematis that don't need pruning, if its easier to move house with them cut down, cut them down - they should just produce new growth off the roots next year and with luck, just flower later.