This weekend, the Sub Center and related sites such as registeronce will be down for a maintenance upgrade.
The scheduled downtime is from 12 Friday 4PM PDT to 14 Sunday 5PM PDT.
In EST, that’s from 7PM Friday till 8PM Sunday.

The new Create Service Request form will include several changes. First, when you fill in the form, you’ll be asked to pick your Issue from a drop-down list. For example, the Issue might be “Software won’t Start, Crashes or Hangs” or “Need technical assistance with Licensing” or “Suggesting a Change in the product”.

Next, and more interesting (at least to me), is that when you submit your SR (service request), the system will automatically search the autodesk.com KB for the answer to your question. Whatever you type in the Summary box will be used as the search text.