Now I've uploaded the photos, it looks a bit rain-battered! It DID look very good a few days ago! :-))

Hello, did not see this question below your other one, i would let it get going a little before pruning, this belongs to group 2 pruning, and can be pruned in the early spring, but you dont need to be ruthless, come down on some of the long shoots to healthy pairs of buds, this will keep it more compact lower down rather than all the flowers being high up and the base all bare, this clematis if old and very bare at the base, can be cut hard back to a couple of feet from the ground and will send new shoots up, let it get more established before pruning.

Thanks Julien! I thought I'd prune it back a little after flowering, as you say. I'm just pleased it flowered at all...did absolutely nothing last year!