Run_N, I am right there with you!! I had the same issue last week.
The last time this happend, it was at 22K miles. They reset under warranty but didn't fmware update. Well now at 45K it happend againg (~passing at 85mph/5600rpm) no update.

The pisser was that they charged me $75 to reset w/o a fix.

I will use AutoZone or buy a scanner next time ($69 on ebay). What is the value-add of the dealership when this happens every 20K miles and they reset.