Oh dear. My saga continues I'm afraid.
On Wednesday Southend Audi applied the same procedure to my car that was applied to Peter's. Mine is a Q3 Sport, Peter's is a Q3 Sport S line, I think. I had a Q3 S line last time but not this!
Anyway, my fix was OK until the next day when I found that MMI had reset overnight exactly as before. It has repeated this 3 or 4 times now, so it definitely didn't work on mine and the Service Assistant Amy said it had been performed in exactly the same way as on Peter's (not sure if it was the same technician).
Apparently, and this is third hand, they put the car into "sleep mode" which I presume is like an "engineers" mode in order to force in an update of some sort. I presume it's a temporary fix to something else. The story is that this secondary "fix" would normally be applied automatically with no problem during car down time, but something goes wrong, it's not applied and it leaves the MMI in a reset state. As I said, I got this third hand and it may be wrong or grossly over simplified. I put it here because I just wonder if anyone was told something similar.
Not sure what to do next, just pondering at the moment.
It's a pity we can't get hold of the internal Audi memo on this to review all the info first hand, but I guess that ist verboten!