Picked up the top super full of honey and miraculously empty of bees - the Porter escapes had actually worked.
There were a few dopey-looking bees still on the comb, but a quick blast from the smoker (and a few unfortunate gouts of flame, but there you are) and Hey Presto!
The advanced kit list for transport included two black plastic bags and an old wine box, which seems to work well. I replaced the super with one filled with blank foundation. Something tells me that this may be a mistake, as the bees may now expend their remaining energies trying to build up stores when there really isn't any pollen or nectar at this end of the year.
Pic from http://www.carrierbagshop.co.uk/product/carrierbagshop/plastic_bags/PL023/Black+Plastic+Carrier+Bags+with+Punched+Out+Handles.htm