That would be a ludicrously quick turnaround for a fix for that incident and also, if a software patch could address that, I'd like to think we'd be looking at a recall.Quite likely it is a small patch to fix a bug - go back a few threads to the unfortunate owner who had a complete cut-out for no reason. I would quietly hope that one of the boffins at Audi went through the returned ECU, found the bug and making sure that we are spared it.
I had this done on my first service as well, I wanted a bit more info and was told that it was a change to the alert levels of oil temp and level. apparently the ECU warning could come on a bit early for low oil level and oil temp. So the update changes the values. I hadn't seen any ECU warning lights at all though.