Less than a month after the Lenovo K3 Note started receiving it, the Marshmallow update has started rolling out to Lenovo A7000. The update not only brings Android 6.0, but also includes the Android security patch for the month of March.
Weighing in at around 1.3GB, the update is being rolled out over-the-air. So, it may take some time before it hits your device. However, if you are feeling impatient, you can manually check for it by heading to the Settings menu on your device.
Oh, and make sure you have 2GB of free space on your device before downloading and installing the update.