HTC is getting better and better at keeping its word when it comes to software updates. The company announced that the HTC One M8 would be getting updated to Android 4.4.3 starting this week, and today the update has begun rolling out over the air for the unlocked and developer variants of the device in the US.

The update carries build number 2.22.1540.3 and comes in at a hefty 592 MB, suggesting some major changes are included in addition to the jump to Android 4.4.3. It’s possible the large size of the OTA file is because it includes newer versions of some HTC apps, like the keyboard and clock apps that went live on the Play Store earlier this week, but we’ll have to wait and see what’s new since the changelog doesn’t offer any details.

As HTC had revealed earlier, the 4.4.3 update also includes the security fixes that Google incorporated in Android 4.4.4. Like all software updates, expect this one to come knocking on your handset sometime in the coming weeks as it spreads out to more and more regions. Should you not want to wait, you can try pulling it manually from the Settings » About phone » Software updates menu.