Okta.idx refresh session using refresh token

Greetings, dear okta team.

During implementation of sign-in flow following explanations from Overview of the mobile Identity Engine SDK | Okta Developer
I’ve encountered no mention of authentication via refresh token. (Although it’s mentioned here to store it safely in the app).

Since the access token can be received only after checking by exchanging success authorisation response. And success authorisation response (with response.isLoginSuccessful === true parameter) can be received, well, after successful authorisation action, I see no possibility to send a refresh token here.

Am I missing something?

Best regards, Roman.