I've rushed twice since the show reopened and have received the same seats both times: F 13-15 in the side orchestra.
"You travel alone because other people are only there to remind you how much that hook hurts that we all bit down on. Wait for that one day we can bite free and get back out there in space where we belong, sail back over water, over skies, into space, the hook finally out of our mouths and we wander back out there in space spawning to other planets never to return hurrah to earth and we'll look back and can't even see these lives here anymore. Only the taste of blood to remind us we ever existed. The earth is small. We're gone. We're dead. We're safe."
-John Guare, Landscape of the Body
I rushed a couple of Sundays ago, and they had lots of seats for us. The first 10 people or so got tickets in the front of the orchestra; I was right after them and got mezz, which is not bad in that theater and actually moved down to second row orchestra at intermission because the show was by no means sold out. It doesn't seem to be a situation where the same rush seats are available each time, but people have reported getting seats as great as front row center if they're at the front of the line, so I'd go as early as you could, just in case.
But no set number of seats or formula, and hopefully the rave reviews haven't made it too much harder to get something decent!