Some airlines seem notorious, however, in somehow not transferring the *Gold and FF details to the boarding pass even though it is in the reservation. I have experienced this more with AC and ET and very occasionally have seen it on other carriers if the first leg of flight was on a different * airline. If traveling in Y and *G not on boarding pass, I will always ask to generate a fresh boarding pass that includes my *status. Sometimes this may not be possible at the originating airport, if a different airline, and may have to be done at the airport in which you are trying to gain access to the lounge. Of note you can also be denied priority boarding if the boarding card does not have *G so another reason to always make sure it is included.