I think 1k is the minimum if you want a chance at getting verified. However, the amount of mail and users have also been going up. So I think that number has also gone up a bit so it wouldn't hurt to send out mail to more people to be safe.
Posted Using LeoFinance Beta
Yes, I didn't know that during the first two tests, that's why this time I wanted to make it 1k. The funny thing is I forgot to input the exact number of emails to be sent. So ListNerds sent 1,570 instead.