CLI BUILDS use 0 build minutes - we aren’t building for you
The limit around authorization is for Identity, not Oauth. If you don’t understand the difference (I don’t always myself ) let us know more about who you are intending to authenticate and how (“my visitor connects to Okta and …” or “my colleagues connect to netlify to create sites via the API” etc), and maybe we can give a better answer.
As for the authentication part, I should’ve phrased it better. I’m more interested in knowing whether there are any limits in free tier (not specifically number of users) for using OAuth providers? In my case, I’ve added Github OAuth provider to a site and that’s what got me curious.