RedirectToIdentityProvider event in Okta middleware

I’m using the Okta AspNet middleware but need to be able to add some values to the state before the redirect to the identity provider occurs.

When using the standard OpenIdConnect middleware I can add a hook into the RedirectToIdentityProvider event and add the values to the state at that point but the RedirectToIdentityProvider is hidden away when using the OktaMvcOptions that is available in the Okta middleware.

Is it possible to hook into the RedirectToIdentityProvider event (or something similar) within the Okta middleware?

Thanks,
Simon