USB Type C swap A/B rows for easier routing
Let's say you connected the receptacle exactly as it is shown on your diagram. Then you attached the cable and marked corresponding pins on both plug and receptacle, A1..A12 in top row, B12..B1 in the second row.

Now, if you disconnect the cable, rotate it 180° and plug it back, pin marked A1 on the plug will be connected to B1 of the receptacle. Pin marked A2 to B2 and so on.

So, if you now swap the signal traces the same way, i.e. A1 &lt;-> B1, A2 &lt;-> B2 ... then the end result will be electrically identical to the original connection. Your SoM will not see any difference, but the routing will be more convenient.

Note, that the same result can be achieved by rotating SoM in place, but since you said it is fixed the swapping of the traces is a way to go.