The ROM version number is 6.14.707.1 consists number of bug fixes and changes have been made on the way to Asia. The update weighs in at a hefty 1.14GB. US Variant of HTC One M8 has received update more than a month ago.
HTC One M8 Asia users can go to Settings >> About Phone >> System updates >> check to get the update. Users in India can also check or wait for a week to get the update notification. The update to Android 6.0 Marshmallow brings app permissions, Doze battery optimizations, and Now on Tap. There are also many other changes that you will notice.
If you haven’t received an OTA update notification. You can manually check or wait for few days.