Well, it didn't take long to confirm the firmware update didn't fix the problem. A week went by with several rides, but about 50 miles into today's ride it failed as before. I scanned with my GS911 when I got back home, but there were no fault codes. That was a bit of a surprise. I'll contact the dealership and see if I can get them to replace the shift assist hardware module, although at least one other forum member has reported that was done without remedying the issue.