I rushed Part One yesterday, and got to the box office at 11AM, and purchased EE4. Today I didn't get to the box office for Part Two until 2:30, but was able to purchase B23 in the mezz. My seat tonight was considered partial view, but I saw everything just fine. I really loved the show, and it was close to being sold out both nights, so I'm glad I was able to rush it.
I rushed Wolf Hall on Saturday. Got there at 9:45 and was the 4th person in line. No one else showed up by the time the box office opened at 10. You are able to get rush tickets for both parts (for the marathon). My tickets were located in one of the box seats. slight partial view aka missing the back corner of the stage where not much action takes place. Good seats in my opinion.