In your case, one car being on FSD and the other not, is enough to explain the difference, particularly if you have been on the FSD beta track. I think @fasteddie7 is saying that the updates appear to come to all cars on his account simultaneously (the interesting fact) but obviously only if they can, based on other considerations.Not my experience, my wife's car and my car has never gotten updates on the same day or even within the same week. My car has FSD and USS but hers doesn't though.