More progress - I finished 7 more black orcs last night (bringing the total to 10) which means I'm now halfway through the unit. As I sat back to admire my work I had a Homer Simpson moment.
Half of the miniatures I have finished have a prominent mould line across the armour plates on their shoulders. How can I not have spotted this before! Well, its too late for this batch but I can do something about it on the remaining 10.