For a very long time it has been possible to, either at the gate or preferably in the KLM Crown Lounge, for a fee buy up to Delta One from most fare classes for either cash or cash plus miles.
The plus side of this is you are flying Delta One for a tiny fraction of what it would cost you to outright pay for a business class ticket last minute. But there have been issues with this practice as it has often meant those who wanted to use their valuable Diamond Medallion Choice Benefit Global Upgrade Certificates couldn’t because Air France or KLM had sold out any open seats (and from my understanding, keeping the proceeds).
Well, according to Hollandair on FlyerTalk that has changed as of the 1st of the year and that you can no longer buy-up for cheap as you could in the past. Now it seems you can only use your Global Upgrades on Delta flights but on KLM flights you can still use miles or your Global Upgrade certificates.
Why this change? My guess is twofold. First off, with the change to allow you to upgrade just about any ticket with SkyMiles as of 10DEC18, Delta wants to control the cost of the upgrade and to realize the gain from you spending SkyMiles to upgrade vs. giving the money to AF/KLM (remember, Delta views you spending SkyMiles the same as spending cash). Next, I am sure Delta is sick of endless complaints from Diamonds who have open seats gamed away from them by the Skyteam partner rather than processing their earned upgrade certs. As a Diamond I am endlessly frustrated with Delta releasing so few seats for Global Upgrade Certificate use. To at least have a realistic shot at using them day of departure is a nice change.
What do you think of this change? Have you purchased cheap AF/KLM Delta One upgrades from Europe to the US? Do you ever buy-up on AF or KLM flights from the US? – René