I've tried a second and third module and it's exactly the same (see attached) - although all the modules came in the same pack so that may be saying too much.
The chip is MAX485 ESA +18DN if that makes any difference.
When I look at your image versus mine, they look exactly the same but the mirror image.
With the exception that the test channel is not the mirror image.
I really don't know what that means.
I'm looking to see if there's another, different module I can get quickly and cheaply for comparison...