I just flew Swiss and took an extra suitcase using my A3*g,but when I wanted to change my ff # at the gate to united, the gate agent(who was the same guy who checked me in) refused ,saying that if I change my A3 num,he will charge me for the extra suitcase I took!! No arguing was able to convince the guy.....
Another wierd thing with Swiss, was that even though my wife is A3 *g ,and had I had a printed email confirmation saying that(we didn't get the card yet), on the Swiss system she only came up as A3*s....