Anyone will be able to be a judge, but judging won't open until the game submission deadline at July 5th 2019 at 5:00 AM PT and closes a week later.
I believe that you'll be able to download and play any submissions before the deadline, so you won't necessarily have to cram playing everything into one week. I'm actually not sure what the normal time frame for judging is so I'm willing to extend that, especially if we get a ton of games submitted.