The “select developers on API usage tiers 3-5” that the blog post mentions were chosen on Weds, meaning, if you reached tier 3 or higher after that, you won’t have access today. It’s not automatic, and I’m sorry that this wasn’t clearer earlier.
And that said, being in one of these tiers does not guarantee access immediately. For safety and security reasons, I can’t disclose all the eligibility criteria—but the “select”, established developers within those tiers that receive access first are those that are known to be using the models in good ways.
We’ll be doing more passes next week and so forth—both in giving access to more developers within tiers 3-5 and adding any new developers who recently reached tier 3 (and you’ll receive an email once o3-mini’s been enabled for your account).