One of the interesting things I've read about Tesla's OTA updates, is that for common sense "holy shit that was not supposed to happen" type reasons, they push updates to discrete batches of cars at a time, wait to make sure that owners are not reporting weirdness at a rate any higher than the normal background noise, probably do some analysis on the self-reported telemetry, and then proceed with pushing updates to additional VIN numbers.

It's definitely not a "push to all cars" type thing.