It seems to me that A3 should re-write their rules in a very clear fashion and ask their agents to strictly abide by them without using their fantasy to justify their decision. My son flew recently SYD-SIN-MUC-ATH (coach) on SQ/A3 with an A3-issued ticket on which the first two legs were indicated with the A3 code-share number. He was refused a coupon-upgrade for the third leg the excuse being that you can only do it when the major carrier of the itin is also A3. Actually, their written rules say that all legs have to be flown on A3, i.e. the code-shares do not count. Now, why they have that clause is completely strange. Go figure...