What mandates an upgrade?
Upgrades to higher class travel suites are rare, but they do happen. If you’re a frequent flier, you have a better chance of getting upgraded, granted, of course, you’re not rude. You can further your chances of getting an upgrade should it arrive if you’re courteous, attractive, tall, elegantly dressed, pregnant or are a friend of one of the flight attendants (or pilot). Don’t hold your breath, though, because there’s a lot involved in the process: it’s not just calling up a random lucky passenger.