<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by wideman:
So, even if you had a 'B' ticket, you could have changes the date of your flight, as long as the return was 3 days in advance.
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The advance purchase requirement applies only to the outbound flight. Once you've taken the first flight, advance purchase restrictions don't apply to changes, even for the most deeply discounted fares.