As a reminder, Google releases monthly security updates for Nexus phones so at the very least, you should be getting a security update in November. Whether or not it has bug fixes on it is another story.
Google typically releases its first bug fix update about a month after an update's release so you should be on the look out for Android 6.0.1 in November and December. Googe may not announce its arrival so you'll need to be on your toes.
Just remember, bug fix updates sometimes bring problems of their own so you'll need to come to the next Marshmallow release prepared.
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