Originally Posted by cre95

You can find out whether there is upgrade space available right now by calling or being logged in where you値l see the tag saying that upgrade is available with a global upgrade certificate. With this approach, you値l book / pay for the flights and apply the upgrade. You値l also want to make sure your ticket is reissued in the upgraded class. Your upgrade will be certain.

If there is no upgrade space available when you call, you can still purchase the tickets but you値l just be waitlisted for the upgrade. This may clear before check-in the day prior to your trip or if that doesn稚 happen, you might still clear at the gate. In both of these cases, you may or may not ever clear to the upgraded seat.

Given your flexibility of dates and destination, you could take the first route above and search for an option with the two upgrade-able seats. You値l then be certain of having confirmed upgraded seats.