Android 6.0 Marshmallow, also known as Android M, has begun rolling out to HTC One M9 handsets in the U.K. The release of the update comes a month after HTC One M9 smartphones in the U.S. got a rollout, but only for the unlocked (non-carrier) versions of the device. Could the update release date for Android M on HTC One M9 devices sold by Verizon, AT&T, and other carriers in the U.S. be coming soon?

We'll see. Momentum in the update process has certainly picked up, as the HTC One M9 in the U.K. is receiving the OTA update now, but also starting with unlocked versions, according to a recent report from TechnoBuffalo.

But carrier rollouts are just behind the Android M rollout, as was confirmed by HTC U.K.'s official Twitter account this week.

"We've begun rolling out the Android 6.0 Marshmallow update to the unlocked One M9," HTC's tweet confirmed, adding "and selected carriers so you should see the update soon."

The inclusion of even some "selected carriers" in the rollout is a hopeful sign that carrier versions of the HTC One M9 in the U.S. could also begin getting the update sometime soon, now that a month has passed since the unlocked variant got its update release date.

The Android 6.0 Marshmallow update comes along with an upgraded version of HTC's custom user interface layer, HTC Sense. Android M is the first major firmware upgrade for the HTC One M9 since its release, and includes Google Now on Tap, the battery saving "Doze" mode, and more granular user control over app permissions -- along with a lot more improvements under-the-hood that should deliver a more stable experience and better device performance.

The updates are finally starting to roll out at an increasingly quick pace for HTC, Samsung, and other non-Nexus devices that have been waiting for Android 6.0 Marshmallow since its introduction late last year. Stick with Latin Post for more updates on more smartphones as they happen.