Sprint has started rolling out the Marshmallow update to HTC One (E8) units on its network. The update bumps the device’s software to version 3.10.651.6 and also includes “all current security patch updates,” according to the information provided by the carrier.
As is usually the case with OTA roll-outs, it may take sometime for the update to hit your device. Meanwhile, if you feel impatient, you can check for the update manually by heading to your handset’s Settings menu. Sprint says the roll-out will be completed by August 29.