Having just purchased an E92, I was looking at a variety of diesel models. The recent 320d with manual transmission has auto start stop. The automatic does not. I could only find 325Ds and 330Ds in automatic versions and none of them had auto start stop.
It actually disables itself quite a lot in my car. For example, it doesn't start working until the engine has warmed up. It also disables itself if the temperature is 3 degrees C or less. Finally, if you're stuck in queues of traffic for long periods of time, it disables itself to prevent draining the battery.
Obviously a quick press of the button under the radio also switches it off if it annoys you to the point where you can't live with it.