When you check the "Ask a Question" link, the most recently asked question listed is 3 months old. That seems unlikely. It also seems odd that the Nexus 5 Updates page is current, while the Nexus 6 page is about as far from current as the questions asked about the phone.
The forum is still active. It probably does not get much use because T-Mobile does not sell Nexus devices.
You can view the Nexus 6 forum posts at Google Nexus 6.
You can view all forums on one page (this is what most forum regulars do) here: https://support.t-mobile.com/threads?filterID=all~objecttype~objecttype%5Bthread%5D
From the nexus 6 page, you can click on "update available" link in the "software info" section. This links to the 6.01 firmware. You can visit this page directly at Software versions & updates: Google Nexus 6.
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