I am a Premier Platinum member with United and sometimes when I change my flight online at united.com I am not assessed a change fee and other times I am. Why is that?

United, like other major carriers, has a $200 change fee for domestic tickets and a variable change fee for international tickets, and does not waive or reduce these fees based on frequent flyer status. However, for Gold, Platinum, and 1K level travelers United does waive the “”same day flight change fee”” to change to an earlier or later flight on the day of travel. So, if you want to change your flight a week ahead of time you’ll pay the same fee as everyone else, but if it’s just a case of your meeting runs long and you want to confirm yourself on the next later flight home, you can do so without a fee. To qualify the change must be made before the original departure time, the routing must be the same, the flight must be operated by United or United Express, and the change must be done by United. If the same fare class is not available on the new flight you will be charged any difference in the fare.