While most Google Nexus devices have gotten the Android 6.0 Marshmallow, or Android M, update, most of the Android world is still waiting for the update to rollout to their phones. But according to a new report, Android 6.0.1 Marshmallow is already starting to roll out to some Android One phones.

The Android M 6.0.1 update has a build number of MMB29K and is already gracing the Cherry Mobile One G1, General Mobile 4G, and I-Mobile IQ 2 in some parts of the world, according to Android Police.

If those Android devices aren't familiar, and don't strike you as a list of flagships, that's because they're all part of Google's Android One project, which seeks to bring affordable Android smartphones to developing parts of the world. As part of the Android One project, those phones operate on stock Android and are meant to get operating system updates from Google quickly.

Quickly, indeed: some already have Android 6.0.1 Marshmallow while the Android 6.0 Marshmallow update is just beginning to roll out to flagships from Motorola, HTC, LG, and others.

The update seems to mostly be available as a flashable ROM on XDA (which requires some technical skill to update phones), but one Android One user in the Philippines reportedly received the update for his Cherry Mobile G1 via OTA notification. As Android Police noted, it came with a request for confidentially, which was not exactly honored.

Despite screenshots of the update making their way to Android Police, little is known about the technical details of the Android 6.0.1 update. It is most likely an update to squash some bugs reported during the rollout of Android 6.0 Marshmallow, though, and probably doesn't include any cool new features.

What we do know is that the update is as an Android security patch for Dec. 1, 2015, which could indicate when a larger OTA rollout of this latest Android M update may begin on Android One phones -- and perhaps for Nexus devices in the U.S., as well.