My understanding is that the bleachers in the permanent stands on either base line will be available for GA tickets if you get there early enough.

There were not many reserved seats available. I was worried they would all be gone as part of the pre-sale to top-tier annual HSF donors ($18K+ per year), who were able to buy 4 each. I was logged in before 12:00 and the "Buy Tickets" page for the all-sessions pass had a comment saying tickets would be available to me at 12:00. When I hit F5 right at 12:00:00, there was a link available. I'd say maybe 10-15% of the seats were available then.

I'm not sure what happened that prevented you from buying right at 12:00 if you had donated to HSF for this year. We are Platinum, but my understanding is the 12:00 presale was available to all HSF donors. If you log onto the ticket site now, does it say that tickets will be available for you at 2:00?