So another issue that may arise with this update if it throws an error when they do the recode is the car just wont charge. I had planned to put it back on the charger after they finished the TSB but couldn't get it to start charging. They took it back and applied the TSB again and it ran with no errors and worked. I guess the first time they had told it to retry when the error popped up or something and it was able to complete successfully, but it clearly wasn't quite right. If you're there for service on an EV they'll have a charger in the shop. May be worth asking them to throw it on the charger and testing before calling it done. This TSB is also known as 2040470 v931501. Your invoice may have either number on it. It's the same TSB.
Also, while the car wouldn't charge after the first run of the TSB, I noticed the charger plug didn't actually lock to the car. Of course after they reran the TSB it locks again. I'm not sure if this has something to do with the fact that it wouldn't charge, so it didn't engage the lock. Which is probably the case.
I'm wondering if something similar happened when they initially ran the TSB on your car Mille.