The requested expiration interval (in minutes) for the refreshToken generated by the OAuth request. Set this to RefreshTokenExpirationInterval.Maximum for getting the maximum refresh token supported by the portal (ninety days). The max interval can be overridden by the portal administrator. To set a specific time in minutes use RefreshTokenExpirationInterval.Minutes If this is not set, RefreshTokenExpirationInterval.Default will be used and then the refresh token will be valid for two weeks.