A passenger on a WestJet flight from Cancun to Toronto learned the hard way that there is no price for an onboard upgrade. On a Sunday evening flight (WS2555) from Cancun to Toronto Pearson, a man approached cabin crew shortly after takeoff and offered cash to be moved into the premium cabin. The flight attendant declined, explained the airline's upgrade policy, and the passenger responded by getting verbally aggressive and agitated.

The crew told the captain, who was briefed on the situation, and the man was monitored for the rest of the roughly four-hour flight. He eventually calmed down, no diversion was needed, and the Boeing 737 MAX 8 landed safely in Toronto in the early hours of Monday morning. It is not known whether he was met by police on arrival. WestJet, reached for comment by Simple Flying, did not immediately respond.

The incident is a useful reminder for anyone flying the route: WestJet simply does not sell upgrades once you are in the air. There is no cash-for-seats conversation to be had at 35,000 feet, and trying one is more likely to land you on a crew watchlist than in a premium row.

The legitimate routes to a better seat are all pre-flight. After booking, you can bid on a Premium or Business class upgrade through the airline's auction system, with bids accepted up to 54 hours before departure. If your bid wins, you get an email and your card is charged. Closer to the flight, online check-in opens 24 hours out and sometimes reveals unsold Business or Premium seats available to buy outright. There is also a last-minute online auction running up to 24 hours before departure for remaining premium seats.

WestJet's Cancun network shows why this route is so busy. The airline flies to the Mexican resort city year-round from seven Canadian cities — Calgary, Edmonton, Montreal, Quebec City, Toronto, Vancouver and Winnipeg — and runs a long list of seasonal routes in winter from places like Halifax, Ottawa, Regina and St. John's. It is one of the largest international carriers at Cancun by destinations served. For snowbound Canadians, the four-hour hop south is the classic winter escape, which also explains why premium cabins on these flights are in demand and rarely empty.

For travellers, the takeaway is straightforward: if you want the bigger seat to Cancun, sort it out before you get to the airport — bid early, check in online the moment the window opens, and keep your wallet in your pocket onboard.