Once the excess token is cached, it becomes associated with all the endpoints that are defined in the same service configuration. The frontend generally invokes the APIs via the gateway provided by the platform. The exact URL of these endpoints is unknown to the frontend. The isolation of the API details is one of the critical features of the platform.
The access token is used as long as they have not expired. After the expiry, a new access token is obtained and is placed into cache replacing the old one. The frontend will never know about the expiry and refreshing of the access token.