Brain fade on the above. The bearing would have to be in the wheel hub. This could mean that it involves all of the Super 3s, not just the American ones or could be unique to my car.
I believe there might be an update (recall??) on the UK Super 3's as well. Issue with the make of bearings fitted and lack of grease

The S3 hub is same as the 5 speeder except a bit wider so would assume same quality (i.e filled with grease) aftermarket bearings as can be found on Alt Parts list will also fit.
Well, I have to report that after the clutch of my S3 broke after 2'200km and 3 months of ownership, 3 weeks ago (now 3'300 km) my rear wheel bearing broke
during the drive on a narrow mountain road, which almost sent me down a cliff...
The car is now at the dealership, and I was told that mechanics from Malvern will be coming to inspect the vehicle. So it might have been this incident that triggered the closer scrutiny of the bearing.
I am currently in discussion with the dealer and Morgan to return the car for a full refund, as in my view it is "unsafe to drive". Very disappointed but let's see how the story unfolds.