Earlier quoted context omitted.
Every time I travel internationally I immediately get notifications for Android OS updates. I'm pretty sure they are for satisfying local regulations about the phone's behavior, including the topic at hand.
I am not saying there are no backdoors, but this never happened to me. And I am an Android user since the first G1 phone.
I'm not claiming to know of any foul play, but it has happened several times, enough for me to notice. If it was related to time of the month, it wouldn't be as consistent. It might be that you need specific combination of phone, configuration and network provider for this to happen. Maybe I've been p0wnd, but I've noticed this behavior since at least the Nexus line.