Seems I was too hasty about clearing. I suggest you wait at least 4 days. The top was clear but as the siphoning progressed, so did the murk. Had this problem with the Cal Con kits, which rely solely on chitosan finings, so I used Young's 2 part finings (kiesesol/gelatine) to finish the job, which it did, well almost.
This kit comes kiesesol/chitosan finings but seems no better than just chitosan. This time I decided to filter, partly because the instructions recommend it, partly because it would purge any remaining gas, but mostly, I didn't want the wine hanging around any longer. Filtering did not completely clear it either, but enough for me bung the whole lot into a polypin with no air to worry about, where it can continue to settle and autolyse with the remaining yeast sediment for a couple of weeks, as well as free up the kit for the next batch.
I am in the luxurious position of getting bored with good quality cabernet sauvignon after 45 bottles of the stuff so far, with 15 left and another 30 maturing. I'll go for the Cellar 7 merlot next, with reduced water. 20 l instead of 23 should bring it up to 11.5% and the proportion of grape juice up to about 70%. Throw in those blackberries I got from Azda towards the end too!