Hi there as already mentioned ask at Check In how busy the flight is and whether or not they looking for anyone to upgrade either from Economy - Business or Business - First. I always keep my Gold Card with my Ticket or E Ticket Confirmation and pass it to them when Checking In. Make sure they have your Frequent Flyer number in the reservation as sometimes they don't. Also just check when you get to the gate as they will know by then the exact loading.
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