I think I remember something about a9s tossing out rejections a month or two ago
I saw some stuff about a few random ones... which as fast as you can go on these, I think it's honestly to be expected. On the larger rejection amounts that I read about in the TO.... if I were a betting woman, I would say they probably screwed up using a script trying to make them go faster and it didn't give A9 any results on their end so they rejected the whole lot. I've had this happen to me when I was newer to using scripts so I know it's possible. As long as you're somewhat careful and make sure you're actually submitting quality answers I don't think there's anything to worry about.
Of course there is a possibility that I'm totally wrong... weirder things have happened