Trying to figure out what could have sent an SMS message at a specific time

Crossposted for @madsen

I just noticed in the overview from my mobile provider that I have apparently sent an SMS message to an unknown (domestic) phone number at 03:10 on July 11. Going back a few months I don’t see any other messages to that number.

The number doesn’t belong to any of my contacts, it doesn’t appear to be a premium number (as there was no charge for texting it) or any number I can even look up. And I can’t find the message anywhere in Messages (which is the default SMS handler on my phone) or anywhere else.

Looking at the Permission Manager, only 4 non-system apps are allowed to send and view SMS messages: Google, Google Play Store, Messages and Phone.

So I want to figure out what the hell was happening on my phone that apparently sent a message that doesn’t figure anywhere in the middle of the night. I’ve been trying with dumpsys through adb but I’m having trouble narrowing the dumps down to the relevant date/time and services.

adb shell dumpsys isms had some events from both before and after July 11, but zilch from July 11.

So does anyone know if and how I can figure out what was going on on my phone on July 11 at around 03:10?