Microsoft has moved across the Lumia support section for software updates to its own website



From WP Central:

Previously available on Nokia's online portal, it makes sense for Redmond to move things across post-acquisition of the Nokia handset division. Consumers interested in finding out just when they can expect to receive future updates will now need to head to Microsoft's website, or load previous locations to only be redirected across.

  Lumia update support portal is now available on Microsofts website