public ExpirationPolicy toTicketExpirationPolicy() {
        val rtProps = casProperties.getAuthn().getOauth().getRefreshToken();
        val timeout = Beans.newDuration(rtProps.getTimeToKillInSeconds()).toSeconds();
        return buildExpirationPolicyFor(timeout);
    }
To ticket expiration policy.

@return the expiration policy
support/cas-server-support-oauth-core-api/src/main/java/org/apereo/cas/ticket/refreshtoken/OAuth20RefreshTokenExpirationPolicyBuilder.java