Thanks wombey. Yes, it did have the distinctive, half-white scales on the upper lip which appeared a bit zigzagged at first glance. I’ve posted some other photos of the same snake to show it from different aspects.
The clue to id Copperheads is the white on half each lip scale, never present on Red-bellied Black Snakes. Have a look at images of Copperheads to see what I mean. Mentioning the white on the lips will confirm id every time, colour of the belly is much less help.