Why does this matter so much to you? There is little chance they are lying to you, they likely don't now, IMHE dealers are a bit rubbish at knowing everything. If they've updated the software its probably because there have been improvements. When I take my car in for service, they update it to the latest software, I'd expect that, I'd want that, and unless when I put the car in Drive it goes backwards, I'm simply not worried about it.
Microsoft update Windows all the time, do you check each time the update is applied to see what tiny little things have changed? Of course you don't.
I'm not trying to belittle you here, but pointing out that this seems like worry over nothing.
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