As far as I know the differential lanes are swappable. They each have an identification channel assigned to them, so the combinations are (ACC0, Data1, Data2) a

As far as I know the differential lanes are swappable. They each have an identification channel assigned to them, so the combinations are (ACC0, Data1, Data2) and (ACC1, Data3, Data4). Keeping in mind that the function of each lane is found once it's plugged in the cable becomes fully reversible and routing inside the connector is simpler.