Originally Posted by
Thunderroad
But drewguy, are you sure that the upgrade is to first class and not to business?
Sorry if I wasn't clear: I am almost certain the upgrade is economy-->business. OP may have been confused by the term "businessfirst".
Also individual experiences differ, but generally this route is hard to upgrade, especially F, Sat, Sun because there are a lot of business travelers and elites who fill up the front sections.