Well, I grapple with that myself, so I get it. It’s not that they’re backwards, rather the board is ‘upside-down’.
The confusion comes from the change in the design from the membrane switch to the mechanical switch. My boards have the circuit board traces on the opposite side that the original board does.
Take a look at the image above. The pin numbers do indeed appear to be reversed! The trick, however, is that you are not looking at the same side of both boards. If the bottom (OEM) board is ‘up’ then the HobbyCNC board (top) is down-side-up. When you flip the HobbyCNC board right-side-down, it turns out the pin numbers are exactly right.
The most important part is you DO NOT flip the ribbon cable – it goes back in pin-for-pin in exactly the same orientation as it was originally! Watch the video HobbyCNC Mechanical Fret upgrade, GH 04 install to see how it’s done.