There was an earlier discussion with 'Tell HN' title talking about 625/month. https://qht.co/item?id=22192543
When I access the page I read "Get 5,000 free emails per month". Maybe they're A/B testing?
5,000 a month free for 3 months. Previously, you got 10,000 emails and 100 validations per month included. You had to have a non-prepaid credit card to sign up as well.